Canon Immigrant

The Expanded Universe is a wonderful place, where new ideas can frolic without having to worry about fitting into the Canon. However, sometimes an idea is so interesting that the people who create the canon decide it deserves to become real.

Thus, we have the Canon Immigrant, who is a character created and nurtured in another medium and, eventually, imported back into the original. Note that, often, surface details are brought in to play off a new movie or TV series; this isn't that. Rather, it's usually a completely new character, who over time becomes more and more popular with the fandom, often filling some niche that was never quite complete before. As a recurring trend, these tend to be female characters (likely to be "spunky") who serve to break up an otherwise male Rogues Gallery or ally contingent.

If they're successful enough, they'll be included in new entries in the Expanded Universe, cross-pollinating concepts. Canon Immigrants are often part of an Adaptation Distillation, and new, canonical version usually has extra details to tie them into the more complex backstory of the original.

One should always be aware of the Canon Rule of Cherrypicking and Broad Strokes: the fact that one or two elements from an Alternate Continuity or Expanded Universe have made their way into canon does not make the rest of the Alternate Continuity or Expanded Universe canon, as a whole.

A character is more likely to become a Canon Immigrant, and be embraced as such, if s/he is God-Created Canon Foreigner.

This trope applies exclusively to entire characters or concepts who make the move from adaptation to original material. When dealing with alterations to existing canon that ends up changing the original material, see Ret Canon.

This is what every Canon Foreigner strives to be.

Batman

 * Harley Quinn, from Batman the Animated Series, may be the quintessential example. This Perky Female Minion (and girlfriend) of the Joker was nearly as insane as he, and the dynamic they created was unique among supervillains. After being imported to The DCU, she got her own ongoing series that lasted 38 issues and a major role in the short-lived live-action TV series, Birds of Prey. She went on to co-star alongside Poison Ivy and Catwoman in Gotham City Sirens, as well as appearing in the hit video game Batman: Arkham Asylum, and its sequel, Batman: Arkham City. She currently stars in the new Suicide Squad series.
 * Renee Montoya, a police officer and detective of the Gotham City Police Department, was created for the animated series, but actually appeared in the comics first due to the lengthy production time of the show. She guest starred in numerous Bat-Family titles before being cast as one of the lead characters in Gotham Central, then 52. She also wore the mantle of The Question for a time.
 * Lock-Up also made the leap to The DCU, surpisingly before Harley.
 * Roxy Rocket is a recursive canon immigrant -- she originated in the The Batman Adventures comic based on the animated series, then made it into the series, before finally migrating from the series to the DCU proper as an enemy of Batgirl.
 * Sewer King, also from the animated series, appeared in 52. He appeared in one issue, only to die at the end of said issue.
 * There's Raven, Jay and Lark, the Penguin's henchwomen from the DCAU. Lark was adapted from the comics while Jay and Raven were original characters, and it wasn't until the New 52 reboot that they were made canon.
 * Batgirl is an interesting case. The character was created by DC Comics in 1966, at the behest of Batman TV-show producer William Dozier. Technically, she appeared in the comics (just barely) before her first broadcast appearance -- but she exists only because the television show wanted an "official" young female character fighting alongside Batman and Robin.
 * This is only true of the Barbara Gordon Batgirl. The often forgotten first Bat-Girl was Betty Kane, who appeared as early as 1961. Who was wiped out of canon by the Crisis on Infinite Earths... but was later established in the new DCU as Flamebird. And then both the original Bat-Woman and Bat-Girl were brought back into continuity in Grant Morrisons Batman (though with no apparent relation to either Flamebird or the modern Batwoman).
 * This is even further complicated by Bat-Woman (Bat-Girl's aunt) who was created to be a female counterpart to Batman, while Bat-Girl was the female counterpart to Robin and wore a costume inspired by his. Eventually the two would be more or less merged into each other yielding the more familiar Bat-Girl. The reason both Bat-Woman and Bat-Girl was created, however, was to get around all the Ho Yay brought up by Seduction of the Innocent.
 * The weirdest example is Condiment King: a throw-away joke villain... who got added to the DC Universe as a throw-away joke villain.
 * Terry McGinnis was seen in a few issues, but these were all set in the DCAU continuity (this includes his mini-series.) As of Batman #700, however, he's been inserted in the main DCU timeline as both an alternate universe Batman, and in the main universe as a possible future successor to Damian Wayne. Damian in this case fulfills the role Bruce did in the DCAU.
 * Mr. Freeze existed in the older works, but it was in Batman the Animated Series that his modern characterization was taken from. Even Batman and Robin used that version of the character. Prior to his appearance in the cartoon, he hadn't shown up in comics in almost 20 years
 * Mr. Freeze is a double immigrant, of sorts. He was originally called Mr. Zero but he was renamed Mr. Freeze in the 60s live-action TV show and was as campy as could be expected. He was popular enough in the TV show that this characterization and name was then used for the comic version.
 * Chief O'Hara, a fairly important character from the 60s live-action Batman series went on to make scattered appearances in the comics
 * A comparatively minor case, but Barbara Gordon's role in Batman Beyond led to the now DC-comics-canon-for-the-time-being future depiction that she will eventually take on the role of Police Commissioner of Gotham after her father retires.
 * King Tut from the Batman TV Series appeared as the main villain in a story arc of Batman Confidential, giving him Canon Immigrant status some 40-something years after he first appeared.
 * King Tut also makes an appearance in Batman the Brave And The Bold, which makes him an immigrant from one TV canon to another (or one TV canon to the DCU to a different TV canon. You decide!).
 * Brave & The Bold also went one step further, having cameos by the likes of False Face, Louie the Lilac, Bookworm, The Archer, Marsha Queen of Diamonds, The Siren, Ma Parker, Black Widow, Shame and Egghead. All had a cameo in a prison break, IN ONE EPISODE! All of them were one-shot villains from the 60s TV series.
 * Also, Egghead made the jump to the DCU as well, though looking less like Vincent Price.
 * Averted thankfully in one-time Batman videogame foe Sin Tzu, a should-have-been Ra's Al Ghul character rife with Unfortunate Implications and created with the author *stating* that he could end up like Harley Quinn and make the jump. In short, neither Stan nor Jim Lee can sit down and say, Today I Will Create Fonzie.
 * The DCAU interpretation of Clock King, who was originally a Green Arrow villain, made the jump to the comics as a Batman foe.
 * The Phantasm from Batman: Mask of the Phantasm was modeled after one-shot comic villain The Reaper, who appeared in the now Retcon story Batman: Year Two.
 * The entire concept of Dr. Jonathan Crane (aka Scarecrow) being a former Arkham employee, which wasn't added until Post-Crisis.
 * The Batcave was first created for the 40s Batman movie serials. Before then, Bats' home base had always just been Stately Wayne Manor, with a tunnel to the barn which held his vehicles. The producers of the notoriously cheap serial couldn't afford to build a mansion set, so they re-used a cave set which had been used for a different serial, calling it simply "Bat's Cave." The idea worked so well that the comics began including the hideout within a few months, renaming it "the Batcave." The serials also were the first to depict the passage-way to the Bat-Cave to be behind a grandfather clock.
 * The 40s serials were also responsible for making Alfred's thin, mustachioed look. When Alfred was first introduced, he was rather fat and was clean-shaven (not to mention a lot more bumbling).
 * The Batmobile has had its famous jet exhaust since the 60s series added it.
 * The 1960s live action series and the DCAU version first invented and then popularized respectively Riddler's green and question marked bowler hat and business suit to the point where the comics version is now only rarely seen in the jumpsuit.
 * The Grey Ghost from Batman the Animated Series eventually appeared in Batgirl, only to be killed off in one of the final issues.
 * Batman's childhood friendship with Zatanna was a concept introduced in the 90's Batman show. It was only after Infinite Crisis that Paul Dini (who first introduced the idea in the cartoon) made it canon in the comics.
 * Lau, the Hong Kong banker from The Dark Knight film, made a brief appearance in an issue of Red Robin.

Superman

 * Jimmy Olsen is perhaps the earliest well-known example; he originated on the Superman radio show (though an unnamed copy boy briefly appeared earlier in the comics).
 * Kryptonite Factor also debuted on the radio show, though it was used earlier (as "K-Metal") in an unpublished comic book story.
 * Perry White, editor-in-chief of the Daily Planet, also first appeared on radio and transitioned to the comics -- in 1940, making this fall just barely short of Older Than Television. The name Daily Planet was a radio show invention as well.
 * Mercy Graves, Luthor's Tyke Bomb/Battle Butler from Superman the Animated Series, follows from Harley's lead. Hilarity ensued -- in the literal sense, not sarcastic -- when both began catfighting during the BTAS/STAS crossover movie World's Finest. It was a draw, with a great deal of Clothing Damage. Harley arguably emerged the victor when she taped up Mercy's mouth and strapped her to a killer robot. She proved popular enough that she would subsequently appear in other animated series like The Batman (with some slight changes) and Young Justice, and heavily inspired the character of Tess Mercer from Smallville.
 * Perhaps as a nod to her origin's debt to Batman, she made her first DCU appearance in the Batman crossover Batman: No Man's Land.
 * Shock and Awe-powered Livewire -- again, a spunky young female villain -- is Superman the Animated Series' major immigrant. The series' few other original characters (Luminus, Mala) are just stand-ins for mainline DCU characters (Dr. Light and Faora/Ursa, in those cases)
 * Mala does owe her name to a male character who debuts in the Silver Age, but yeah, the show's version was basically Ursa/Faora.
 * Smallville: Following the Infinite Crisis reboot of The DCU, Clark Kent spent his teenaged years dealing with various mutant villains created by the Green Rocks that accompanied his spaceship. Also, Luthor grew up in Smallville (though this had already been established in a previous storyline, it has been repeatedly retconned back and forth).
 * DC Comics has made several in-continuity winks to the character of Lionel Luthor, Lex's father. In one instance, Lex hired an actor to play the part of his foster father in order to enroll him at Smallville High School. The actor in question bore a physical resemblance to Lionel Luthor. It has since been established that Lionel Luthor is Lex's legitimate father in canon DC Comics continuity. However, instead of being a wealthy businessman, the comic book version of Lionel was a blue collar alcoholic.
 * There were plans for Chloe Sullivan to make the jump to the comics following Infinite Crisis, but ultimately it fell through. She eventually showed up in a Jimmy Olsen feature.
 * As an in-joke, the Smallville versions of Clark Kent, Pete Ross and Chloe Sullivan made a cameo appearance in the first issue of Geoff Johns' Teen Titans run.
 * The Modern Age of Comic Books marriage of Clark Kent and Lois Lane may seem like this, since it was timed to coincide with the characters' marriage in Lois and Clark. However, the writers had actually been planning to marry them beforehand, and were made to postpone it until the show was ready. (What did they do in the meantime? Killed him off and brought him back, of course. Some things a guy's just got to do before he gets married.)
 * Professor Pepperwinkle from the 1950s The Adventures of Superman TV series is a similar case. He made his first appearance in the comics in 1974. This was probably helped by the fact that the TV series was commonly rerun in syndication, so readers who weren't alive in the 1950s were still likely to recognize him.
 * Ursa and Non from the movie didn't come to the comics until 26 years later. However, they were based on Quex-Ul and Faora, two Phantom Zone criminals from the comics. Zod was an amalgamation of the comics' Zod and Jax-Ur.
 * Inspector Henderson first appeared in the Superman radio series in the 1940s and later in The Adventures of Superman television series in the 1950s. He eventually appeared in the Superman comics in the 1970s. Since then he has turned up in Lois and Clark and Superman the Animated Series.

General DC Comics

 * A number of characters from Kingdom Come have found their way into the main DCU continuity, including Cyclone and Magog.
 * Literally, the KC version of Superman fell through a Negative Space Wedgie into the main universe.
 * In a less literal sense, for years many characters were written to resemble the Kingdom Come versions of themselves more; Nuklon becoming Atom Smasher, Mary Marvel's costume change, and more.
 * The mainstream continuity Superman temporarily adopted a black background for his chest emblem like his KC counterpart. Like his KC counterpart, it was to mourn mass death (in this case from the Our Worlds at War storyline.)
 * And prior to the above Negative Space Wedgie KC Superman Batman and Wonder Woman came to the past to meet their mainstream counterparts (which made Kingdom Come for a time the official future of the DC Universe.) Now it's an alternate earth where the events happened concurrent to our present.
 * The Kingdom story didn't establish it as "the official future", instead it was the story that introduced the little-used concept of Hyper-Time. The Kingdom Come characters assumed they were the actual future incarnations of the characters, only to find out by the coda that they were actually just visitors from a vast tapestry of alternate timelines which sometimes feed into the canonical DC Universe. Sharp-eyed readers will recall that clues were being planted that something screwy was going on with the DCU Timeline as far back as the New Years Evil and DC One Million stories.
 * Más y Menos from the Teen Titans animated series were original characters for the TV show who have since made appearances in the comics. Cinderblock was also created for the show before appearing in the comics.
 * Isis from Secret Of Isis, although it took nearly 30 years to do it. The series 52 features a DCU version of the character as a probationary member of the Marvel Family,.
 * Wendy and Marvin, from the Superfriends, were introduced in The DCU in 2006 as caretakers of Titans Tower. However, they were super-genius, black-haired twins, so they had really little to share with the originals (not necessarily a bad thing). In an ironic twist,  Wendy later went on to appear as a major supporting character in Batgirl, but was written out of the book just prior to its cancellation. After their comic book debut, the two were also brought over into the Young Justice animated series.
 * Samurai, a Japanese superhero introduced in the same cartoon, would later be brought into the DCU during Brightest Day.
 * Before that, the Wonder Twins were members of the Justice League International spinoff group Extreme Justice, and reserve members of Young Justice.
 * It now appears that Apache Chief is being brought over into Young Justice, albeit with a modernized, less-stereotypical personality and origin.
 * Steven Mandragora was created for Justice League Unlimited as a Captain Ersatz for Black Lightning's archenemy, Tobias Whale, and in the DCAU was the murderer of Huntress's parents. Huntress Year One has Helena trace her parents' murder to the Boss of Bosses, Stefano Mandragora.
 * A number of Teen Titans characters got Canon Immigrant costumes, finding themselves redesigned to resemble their animated counterparts.
 * And to complete the circle you have the Alternate Universe in the Teen Titans cartoon comic where elements of the characters' original comic predecessors are integrated into their current designs; Aqualad as a Hook Handed "Tempest" and Speedy as the goatee-sporting gunman "Arsenal" being the most obvious examples.
 * The DC Nation shorts did this once again due to Mad Mod's powers turning back to time.
 * Jackson Hyde/Kaldur'ahm, the second Aqualad and son of Black Manta, was introduced during Brightest Day months before the Young Justice cartoon show he was created for debuted (thus making this case similar to the Barbara Gordon Batgirl, who was created for the 1960's Batman show but debuted in the comics first).
 * The Milestone Comics characters have been incorporated into the DC Comics universe, thanks to Static's popularity. The Dakota-verse was merged in with an in-universe Retcon, and only Icon and Superman know the truth.
 * Additionally, Static later adopted the second costume he wore in the TV series when he joined the Teen Titans.
 * In her first appearance in the DCU following the controversial DC reboot, Miss Martian is shown wearing her stealth outfit created for Young Justice.
 * The post-Flashpoint reboot of Firestorm integrates several concepts that were introduced when the character guest-starred on Batman the Brave And The Bold. First and foremost, Ronnie and Jason now gained their powers at the same nuclear accident, and Jason is now a genius.
 * The sentient space cruiser Aya was introduced in the Green Lantern comics just prior to the New 52. Aya was created by Bruce Timm for Green Lantern: The Animated Series, but like Batgirl and Aqualad, appeared in the comics first.
 * Persephone, one of the Amazons from the Wonder Woman animated movie, appeared in several issues of Gail Simone's Wonder Woman run. This was likely due to Simone having written an early draft of the film's script.

Marvel Comics

 * S.H.I.E.L.D. agent Phil Coulson first appeared in the films Iron Man, Iron Man 2, and Thor and The Avengers. He has since appeared in the Ultimate Spider-Man cartoon.
 * As of the "Battle Scars" mini-series, 616 Nick Fury has a son named Marcus Johnson, who bears a suspicious resemblance to the Samuel L. Jackson-inspired Ultimate / film-verse Fury. His name even was later revealed to be Nick Fury, Jr.
 * In a two-fer, the name of Marcus' friend "Cheese" is actually Phil Coulson. Yep, the "Son of Coul" is officially in Earth-616.
 * X-23, from X-Men: Evolution, who was a cute, female (note the trend!) clone of Wolverine, similarly crossed the animated series/comic book barrier (and appears in Marvel vs. Capcom 3). She wasn't the only original character on the team, but was much more popular than Spyke, Storm's nephew who was essentially a male Marrow who even joined the Morlocks at one point.
 * Though he did inspire two similar characters. A modified version of Spyke named "Spike" was a member of the X-Force, but he fell prey to the team's infamously high turnover rate. More recently, a canon nephew for Storm named David (Spyke's name was Evan) was introduced, though it has not yet been revealed if he is a mutant.
 * The mutant superhero Firestar was created for Spider-Man and His Amazing Friends and, like Spidey's other amazing friend Iceman, was supposed to be a former member of the X-Men. She was imported into the Marvel Universe in X-Men #193, and later served as a member of the New Warriors and The Avengers.
 * Also it should be noted that the Ultimate Marvel version of Firestar has joined the X-Men, so the circle is complete.
 * Aunt May's dog in Amazing Friends, Ms. Lion, became a member of the Pet Avengers with one small change.
 * The Pac-Man Fever villain Video Man appeared in one issue of Spider-Man Family, which was basically a long Mythology Gag to the show.
 * In The Fantastic Four cartoon series of the 1970s, the Human Torch was replaced by a Robot Buddy named "H.E.R.B.I.E.", not (as one rumour stated) because the producers were afraid children would immolate themselves trying to imitate the Torch, but because there was a solo Human Torch movie deal in the works at the time. Assorted versions of HERBIE have since appeared in the comics as an example of the sort of random stuff Reed Richards invents between adventures. (In the most recent cartoon, "Herbie" is the name of Reed's computer.)
 * Herbie is currently Franklin Richards' robot guardian, at least in the Franklin Richards one-shots and Power Pack minis.
 * HERBIE's been depicted pretty regularly lately as a model of robot that Reed produced dozens of to perform various odd jobs around the Baxter Building.
 * Here's one that's actually in canon. In X-Statix, Latin Lover El Guapo was a character added to the X-Statix movie to help it appeal to a broader audience (there aren't many traditionally attractive men on the team), and to hold the Conflict Ball by, in being so handsome, disrupting the other characters' relationships. However, the actor playing him is an actual mutant who eventually is asked to join the team for real as El Guapo. He proceeds to do the exact things movie El Guapo was created for, completely on accident.
 * The 90s' X-Men animated series gave another interesting example in Morph. He was based on a comics character, Changeling, who had been killed in the 1960s, and was Killed Off for Real in the pilot to shock everybody. He proved so popular in his brief screentime that not only was he brought back to life in the cartoon, but an AU version of Changeling who went by the codename Morph was introduced in the comics.
 * Two of them!
 * Reptil, originally a character created just for The Superhero Squad Show toyline (which came before the show, remember), was introduced in the comics in an Initiative special in early 2009, and became a student at Avengers Academy the following year.
 * The Next Avengers: Heroes of Tomorrow debuted in a direct to DVD animated film before arriving in the 616 in Avengers v4 #1.
 * There was a thankfully brief period where Captain America (comics)'s partner Falcon adopted the costume he wore in the maligned late 90's Avengers cartoon.
 * The Mutant Response Division, or M.R.D., first appears in Wolverine and the X-Men, and has since been introduced in the main X-Men comics continuity starting in mid-2010, and has also spread to a mention in Avengers Earths Mightiest Heroes.
 * J.A.R.V.I.S., the AI that replaces Edwin Jarvis in the Iron Man films, has since appeared in the comics as the internal computer of . Apparently, the comics version's personality is modeled on the human Jarvis.
 * J.A.R.V.I.S. has since appeared in The Avengers: Earth's Mightiest Heroes and Ultimate Spider-Man.
 * In a manner similar to Aqualad and Reptil, the new White Tiger (aka Ava Ayala) introduced in Avengers Academy was created for the Ultimate Spider-Man animated series. The new Nova, Sam Alexander, was also created for the show and was introduced into the comics during the Avengers Vs X-Men crossover event.
 * The Anton Vanko version of Whiplash was introduced in the comics in order to have a version of the character similar to the unique take on Whiplash seen in Iron Man 2.

Anime

 * El Hazard featured a goofy and silly version of the "ultimate weapon android" Ifurita, as opposed to the far more serious and angsty Ifurita from the original OAV continuity. However, her popularity led to her being written into the latter continuity via the Radio Dramas, where her name was changed to "Ifurina."
 * Ryo Akiyama from Digimon Tamers and his Digimon don't seem to follow the same rules as the others. This is because he is literally from the Alternate Universe where the Digimon Adventure series took place. This is explained in the series of video games of which he is the star. To drive the point home, he is not in the Manga that was later adapted from the series.
 * Unfortunately for western fans, his games were on the Wonder Swan, a handheld that was never released outside Asia. The first of these games got an English translation for Hong Kong, but the translation sucked. When he did turn up in Tamers, there was naturally massive confusion, as without the games to explain his backstory, he seemed to make absolutely no sense as a character. Interestingly enough, he's a different kind of Canon Immigrant, his games are canon to the Digimon Adventure universe, he cameoed in Our War Game, and then twice in Digimon Adventure 02, and is a vital part of Ken's backstory. He moved to the Tamers universe after ZeedMilleniummon's final defeat, effectively immigrating from one universe to another.
 * Tokyo Mew Mew imported everything but characters from the anime after it Overtook the Manga. The girls originally didn't use transformation phrases, for one...
 * Mai-Otome 0[[S.ifr|Mai Otome 0 Sifr]], the anime prequel to Mai-Otome, features Mayo and Shion, characters originally from the Mai-HiME Destiny Light Novels taking place in an Alternate Continuity to Mai-HiME. A rare example of trans-continuity, trans-setting promotion to canon.
 * Mazinkaiser was born out of the idea of giving the Mazinger Z a Mid-Season Upgrade for Kouji Kabuto in Super Robot Wars F Final. Developer Banpresto asked Go Nagai, Mazinger's creator, to design it; not only were players pleasantly surprised with the upgrade, but the reception of its appearance allowed Nagai to quickly incorporate the Mazinkaiser into Mazinger canon.
 * Mei Sakura, a character created for the Love Hina anime, was not only inducted into the manga at its very end, but Akamatsu then transplanted her into Mahou Sensei Negima, causing many fans to wonder if they're one and the same person.
 * In Detective Conan, Sergeant Shiratori was originally movie-only and Inspector Takagi was originally used only in fillers. Not to mention the large number of minor police inspectors named after their voice actors.
 * In Aria, Ai was originally anime-only character, but starts to appear in special chapter in various guidebooks, culminating in in the last manga chapter (and anime episode).
 * The VB-6 König Monster first appeared in the Playstation game Macross Digital Mision VF-X. Macross Frontier is the first animated Macross series in which it has appeared. Fan theory holds that it got in due to its awesome, gigantic toy.
 * Dragon Ball has one in the form of Goku's father Bardock. Reportedly Akira Toriyama liked the Bardock movie special so much he including him in the manga, in a brief two-panel flashback.
 * Dragon Ball Kai, a recut of the anime which sheds off majority of the filler, actually keeps Bardock's death as the prologue to the series.
 * In Saint Seiya, the special brainwashing technique of the Pope, the Genrou Maouken, appeared first in the anime before being introduced by the author in the manga. Similarl is the case of the character Lyra Orpheus from the 2nd film, who's later seen (redesigned) into the manga continuity (though Kurumada made the design sketches for the movie enemies).
 * Future GPX Cyber Formula: Seiichirou Shiba, Rena Yuuki and Sera Gallagher all first appeared in the PlayStation game The New Challenger and they later were put into the extra ending of Sin.
 * Also Aya Stanford, who appeared in the Sin OVA and some episodes in Saga, was a character originally created for the first SAGA drama CDs.
 * Rai the protagonist of a video game spinoff, or someone that looks very much like him, appeared in Code Geass R2 for a few moments.
 * Similarly, Nonette Ennagram (The Knight of Nine, who's name is derived from two words meaning nine.) appears in R2 when the Knights of the Round are revealed... She never appears again. Some fans have taken this to mean that she's the only Round who hasn't tried to kill Lelouch, and one of the few Rounds to survive the events of the series.
 * Marika Soresi and Liliana Vergamon, two characters used to expound on Cornelia's opinions of events in the novels while acting as her wingmen, appear alongside Britannian Ace and Knight Of Round Luciano Bradley in Code Geass R2. They die immediately.
 * In the Guyver anime film Out of Control, the villainous Guyver II was given a Gender Flip. This female version of Guyver II was incorporated into the manga as another character named Valkyria.
 * The Gundam video game series SD Gundam G Generation features a number of Original Generation mecha in order to spice things up. So far, only one of these has filtered back into the source material: the Gundam Belphagor, from Gundam X's After War time line, which shows up in the sequel manga Under The Moonlight.
 * Gundam actually has quite a lot of these. Mechs that only appear in MSV model kit lines have been showing up in subsequent anime productions since Zeta Gundam, Gundam Unicorn being a particularly massive example.
 * One of the most obscure ones comes in the form of the Perfect Gundam, an armor upgrade for the original Gundam that debuted in an obscure manga called Plamo Kyo Shiro, where it was a kitbash plastic model created by the title character and scanned in to a VR game to battle against other models (a premise later used for the mostly unrelated Gunpla Builders Beginning G). It has since gone on to appear as an upgrade for the actual Gundam in various video games, notably the G-Gen series.
 * In Naruto, a former member of the Seven Swordsman of The Mist is seen wielding twin swords in the manga that originally appeared in a filler arc in the anime.
 * Gari from the Hidden Stone Village, Chukichi of the Hidden Mist Village, Pakura of the Hidden Sand Village and Toroi of the Hidden Cloud Village were all originally from the sixth Naruto movie. They made their appearance in the manga during the Fourth Ninja War arc.
 * Musashi Tomoe from Getter Robo is an example that it might seem surprising to fans, but in Ken Ishikawa's original manga, Getter-3 was piloted by Professor Saotome. Musashi was created to fill that spot in the anime adaptation, and Ishikawa liked him so much that he was imported back into the manga and has subsequently become a central and fan-beloved member of the Getter family.
 * Dororon Enpi-chan is a boderline erotic 4koma parody of Go Nagai's Dororon Enma-kun with with main character being Enma's Distaff Counterpart. In recent remake, Dororon Enma-kun Meramera Enpi is introduced as the main villain and.
 * Minamo from Sketchbook first appeared in the anime incarnation, in which she is Daichi's little sister. She even has a rather big role, interacting a lot with the main character Sora, starting with the very first scene of the series--and she also participates in the art club's events later on. Perhaps the makers wanted to have a younger character to appeal to a larger demographic. She was re-introduced into the manga in chapter 97, about two years after the anime ended. Her first scenes in the manga imply that she has had prior interactions with the main cast, but the author stated in the notes that her Immigration into the manga continuity has no real meaning for the timing.
 * The comics for Wedding Peach featured an upgrade for all the girls to Super Love Angels as an excuse to match their outfits with the ones seen in the anime. The anime had no such upgrade.
 * Trigun: The boomerang-wielding Descartes actually appeared in the first episode of the anime before showing up in the manga Trigun Maximum. Several other one-shot characters from the anime have make brief cameos when Vash flashes back to various people he's met in his journies. Yasuhiro Nightow has actually stated that Vash's encounters with these characters in the anime episodes is canon within the manga's backstory.

Comic Books

 * Cudley The Cowlick, the flying cow head/spaceship from the Archie Comics-published Teenage Mutant Ninja Turtles Adventures comic book, eventually made its way into the original comic book continuity, appearing in a couple of stories. In a bit of a departure from the trope, it was hinted that the Cudley that showed up in the Mirage comics was the same one from the Archie comics, instead of being a different incarnation of the same character.
 * King Toadstool and Wooster, Mario-related characters introduced in Nintendo Comics System, made a few appearances in the Nintendo Adventure Books.
 * Extreme Ghostbuster Kylie Griffin made her way into IDW's Ghostbusters comics.

Film

 * The Moorish character in Robin Hood, who in the last decade or so has cropped up in Film and TV, at least. His earliest incarnation seems to be have been Nazir in Robin of Sherwood.
 * The American Godzilla officially became part of the Japanese Godzilla franchise with the release of the film Godzilla: Final Wars and was even given the official name of "Zilla". Poking fun at the American rendition, unlike all the other monsters, which are depicted as men in latex costumes, Zilla is rendered in intentionally mediocre CGI.
 * He was referenced in an earlier film in which a character asks "Didn't Godzilla show up in New York recently?" and is told "That's what the Americans think."
 * And it doesn't stop there. Mothra, Rodan, Varan, Baragon, Kamoebas (a giant turtle from the obscure film Space Amoeba), Moguera (from another obscure film called The Mysterians), Meganulon, Manda (from yet another obscure film called Atragon) and even King Kong were all stars in their own respective films before becoming part of the Godzilla franchise.
 * Frankenstein Conquers The World
 * It's known as Frankenstein vs. Baragon in Japan. Basically, it takes Frankenstein's Monster (who, not surprisingly, is mistakenly called "Frankenstein") growing to giant size and fighting Baragon.

Literature

 * William Gillette's Sherlock Holmes play introduced the character of Billy the page-boy. When Arthur Conan Doyle later wrote a couple of Holmes plays himself (The Crown Diamond and an adaptation of The Speckled Band) he included this character, possibly for the sake of consistency with Gillette. Conan Doyle later adapted The Crown Diamond into a short story (The Mazarin Stone), and thus Billy entered into the Sherlock Holmes canon. He also received a very brief mention in a couple of the later canonical tales.
 * Happened with Raymond E. Feist's The Riftwar Cycle. The characters of Gorath, Owyn, Jazhara and Jimmy's twin brother Lysle Rigger all make their first appearances in the computer games Betrayal at Krondor and Return to Krondor, set in Feist's world. They were then incorporated into canon when Feist wrote a novelization for both games and made references to them in later books.
 * Margo Lane appeared first on The Shadow radio show before Walter Gibson incorporated her into the prose series. Earlier novels of the Shadow often only barely featured women, but the radio show wanted vocal contrast.
 * Inspector Morse had a Canon Immigrant car. The original novels by Colin Dexter had Morse driving a nondescript modern vehicle, but the TV show gave him a Cool Car, a red 1960s Jaguar Mark II. The car became so iconic of the character that the novels written after the TV show started included it with no explanation of the change, even to the point of putting it on covers (art images, not photos from the show).
 * Ellery Queens secretary Nicky Porter was originally created for the radio show, but later appeared in two of the novels and a dozen short stories.
 * Hastur, a great old one in the Cthulhu Mythos is actually a canon immigrant from The King in Yellow (Well sort of) with a name taken from an Ambrose Bierce story by way of August Derleth.
 * A minor example; The Wizla Tobacco and Rolling Paper Company was first mentioned on the label of Albert's tobacco tin in the TV adaptation of Hogfather, before getting referenced several times in Unseen Academicals.
 * As revealed in the official Mort playscript, rather than try and duplicate the established appearance of Rincewind for the sake of a brief cameo, the Studio Theatre Club replaced him with their own nervous junior wizard character. They called him Stibbons.
 * The Lone Wolf gamebook series had a short-running companion novel series called Legends of Lone Wolf, which basically covered and expanded upon the gamebook stories, including introducing several new characters. Demigoddess Alyss was introduced early into that series, and broke through the canon ceiling in Book 16 of the gamebook series.
 * Doris and Benny the Cab, created for the film Who Framed Roger Rabbit?, appeared in the sequel to the original book. Another character created for the film, Teddy Valiant, is mentioned in the book, though he doesn't appear in either version because he was killed years ago.
 * Who P-P-P-Plugged Roger Rabbit? is really more of a sequel to the film than the book in most respects, including Toons being animated characters rather than comic strip characters,  and being set in The Forties rather than The Eighties.

Live Action TV

 * The first name of Uhura, of Star Trek the Original Series. The name "Nyota" (Swahili for "star") was invented by William Rotsler for his 1982 book Star Trek II Biographies. It was approved by the original actress, Nichelle Nichols, and by series creator Gene Roddenberry. It finally became canon in the 2009 film, Star Trek. As did the names of Captain Kirk's parents, George and Winona, coined by novelist Vonda N. McIntyre in Enterprise: The First Adventure. McIntyre also gave Mr. Sulu the first name Hikaru in her novel The Entropy Effect, and the name was canonized in Star Trek VI the Undiscovered Country.
 * The Holodeck of the Star Trek the Next Generation series, which started its life in Star Trek the Animated Series. Kirk's middle name was first declared as "Tiberius" in the animated series as well (though it was conceived earlier, and Gene Roddenberry had previously used "Tiberius" as the middle name of the title character, William T. Rice, in his first TV series The Lieutenant).
 * Add to that Lady Amanda's surname of Grayson, taken from "Yesteryear," the best known episode of ST:TAS.
 * Minor example: the most prominent new species of the animated series, the Caitians (M'ress) and Edoans/Edosians (Arex), are also canon immigrants: Caitian admirals appear in The Voyage Home and Edosians have been mentioned several times (for instance, Garak dealt with Edosian orchids while a gardener).
 * If plot points from originally non-canon works count, then the big, big one would be the entire episode "Yesteryear". Though the animated series was largely considered non-canon, this one episode gave us a lot about Vulcan culture and Spock's past that has been adhered to - its events were referenced in TNG's "Unification," Vulcan's Forge and sehlats were featured in the Vulcan trilogy on Star Trek Enterprise, and the reboot movie's sequence with young Spock is taken nearly word-for-word from the episode.
 * Synthehol, an alcohol substitute that gets one drunk, but the effects of intoxication can be dismissed at will, started life as a concept in the TNG novels and was soon written into the TV series.
 * Doctor Who has occasionally dipped in its Expanded Universe, largely because of the former fanboys currently in charge.
 * The television episodes "Human Nature"/"The Family of Blood" had their basis in the New Adventures novel Human Nature by Paul Cornell, who also wrote the adaptation.
 * As far as actual characters go, the Dalek Emperor first appeared in Dalek comics and annuals, though he looked considerably different in his first TV appearance in The Evil of the Daleks. When he re-appeared in Remembrance of the Daleks he looked more similar to the comics version, as a Shout-Out. The idea of top-ranking Daleks being gold-painted began in the Peter Cushing films, but made its way into the first couple of colour TV Dalek stories. Speaking of the Cushing films, the new Daleks props introduced in "Victory of the Daleks" take their technicolor design from those of the movies and a couple of design elements (most notably the balljoints for the eyestalks.) from the same comics the Dalek Emperor first appeared. The smallest Dalek time unit, the "rel", also began in films and comics but has been incorporated into TV canon in post-2005 Dalek stories.
 * The look of the Daleks' flying saucers, which first appeared on the DVD release of The Dalek Invasion of Earth as replacement special effects, and later appeared in the series itself, was originally from the comic strips.
 * A glass Dalek was first mentioned in David Whitaker novelisation of the original Dalek story: Doctor Who in an Exciting Adventure with the Daleks. A glass Dalek eventually made it into TV canon in Revelation of the Daleks.
 * While not appearing in the episode, the Chelonians, an alien species first introduced in the Virgin New Adventures novels during the show's nineties hiatus, are name checked as part of the Legion of Doom of "The Pandorica Opens".
 * In a comic about the character Spike from Angel, Spike is sent to an asylum for demons and meets an incredibly strange character... a human-sized, floating, telepathic Betta fish named Betta George. Apparently, when Joss Whedon approached the writer of these comics to collaborate on the canon continuation comic After The Fall, he noted "I like George. Let's find a place for him." The fans are reportedly somewhat squeamish about the inclusion of such a blatantly strange character in canon, despite the show's other eccentricities.
 * Illyria also appeared in another comic's canon.
 * Howard, Marina, and Pearl from Last of the Summer Wine. They started out in a stage play version of the show, and got a good enough reaction to become part of the TV cast.
 * The CSI villain Sqweegel. Anthony Zuiker's digital novel "Level 26 Dark Origins" has first White Sqweegel and at the end comes Black Sqweegel, the one who crossed to CSI. Word of God has confirmed the immigration on Level 26 website.
 * Zordon's home planet of Eltar was mentioned in Power Rangers Turbo after originating in the non-serial first movie. Likewise for the Tengu (renamed Tengas) and the Rangers ninja costumes and powers since the events of the movie were modified and retold in the series. The Zords don't quite count as they were based on the mecha from Ninja Sentai Kakuranger and most likely would have appeared in the series anyways even if the movie was not made.
 * The Battlizer from Power Rangers SPD crossed over to its source material, Tokusou Sentai Dekaranger the same year when they returned for its team-up movie with Magiranger.

Music

 * The Beatles had a problem with the soundtrack to their television film Magical Mystery Tour, as the film had only six songs. In Britain the soundtrack "album" was released as two singles with three songs apiece. In America, Capitol Records added the Beatles' 1967 singles (including "Penny Lane", "Strawberry Fields Forever", and "All You Need Is Love") to the soundtrack to make a full length album. The revised American version has now become the standard version all around the world; the original British edition of Magical Mystery Tour has long been out of print.

Mythology

 * When a new dwarf planet was discovered in 2005, it was given the informal name "Xena" until a proper name could be given. However, the name Xena stuck with people and actually came in fourth in a poll about the new dwarf planet's name. Since the laws state that planets must be given names from mythology (and all planets except Earth are named as such), had the name stuck, Xena would have became an immigrant to mythology.
 * Vampires fear/aversion/weakness of sunlight. In Dracula, the original vampire novel, the count can walk about in the sun just fine, it wasn't until Nosferatu that the sunlight weakness was created, and has become an integral part of future tellings of Dracula. Not that the novel itself didn't take liberties with the lore that inspired it.
 * Although many sources now list among the Norse pantheon a goddess of love named "Astrild", she is in fact the creation of a Romantic-era English poet; the original Norse goddess of love was Freya.
 * The hippogriff made its first documented appearance in a 16th century poem, and it's unlikely that even people who'd sincerely believed in griffins ever gave credence to these horse/griffin hybrids. That hasn't stopped modern fantasy writers from including them in the roster of commonly-appearing mythical beasts.

Newspaper Comics

 * Similar to Clark and Lois' marriage, Jon and Liz of the comic strip Garfield are now the strip's Official Couple after nearly 30 years of non-interest and pity dates on her part. This is mainly due to the fact that the live action movies had paired the two off in the first and married them in the second.
 * Also, Binky the Clown who debuted in the Garfield Halloween Special before appearing in the strip a year later.
 * Floyd the mouse is an odd case. He debuted as a minor character on Garfield and Friends, and appeared in the strip several years after that show ended, but he only ever appeared in ONE STRIP. (January 27, 1998.)
 * Hubert and Reba, Jon's old neighbors. They first appeared in the special Here Comes Garfield, aired October 25, 1982, then started to appear in the strip 13 days after that.
 * The animated Peanuts special, Snoopy's Reunion, aired in 1991, featured three of Snoopy's siblings who hadn't appeared in the strip, Andy, Molly, and Rover. While Molly and Rover never appeared in the strip, Andy first appeared in the strip in 1994.

Professional Wrestling

 * In a borderline case, the main character of the '70's manga and anime Tiger Mask, a masked pro wrestler by the same name, was brought into New Japan Pro Wrestling in the '80's. He's since become something of a Legacy Character -- at least four different wrestlers have donned the mask -- as has his Evil Counterpart, Black Tiger.
 * A more direct example is Suicide, a character who first appeared in TNA Impact!: The Video Game, and later showed up in the ring to exact unspecified revenge on the Motor City Machine Guns. Due to wrestling's self-aware nature, this led the Guns to complain to anybody who'd listen about having been beaten up by a video game character.
 * Tommy Lister, AKA "Zeus", became a pro WWF wrestler after doing No Holds Barred with Hulk Hogan. That venture fared mediocrely, but that didn't stop WCW from bringing him back briefly to fight Hogan as "Z-Gangsta".
 * WCW tried it too, when they made David Arquette champion after Ready to Rumble. This isn't quite an example, as Arquette's WCW run was explicitly as himself and not his character from the movie, but it's close enough to merit a mention. The bizarre triple-cage match that serves as the movie's climax also made a WCW appearance as part of this storyline.

Radio

 * The Big Finish Doctor Who audio plays have their own Canon Immigrants brought in from the comic strips, mostly from Doctor Who Magazine: short episodes feature cuddly alien conqueror Beep the Meep and Time Lord construct Shayde, and there is a short and a full-length episode in which the Doctor's companion is shapeshifting penguin Frobisher.
 * The Company Of Friends is an Eighth Doctor play that features a 45-minute story for two people that were never in the Big Finish audios before -- Fitz (books) and Izzy (comics).

Tabletop Games

 * In BattleTech, Adam Steiner was created for the spin-off cartoon; however, he has since been "adopted" into the canon of the main line, becoming one of the heroes of the Lyran Alliance due to his military exploits and eventually . Other characters from the Cartoon have appeared, but none as prominently.
 * The Blood Ravens chapter of Space Marines in Warhammer 40000 were initially invented for the Dawn of War series of video games, but eventually got accepted into 40K canon due to the popularity of the series, and have since appeared in several Black Library novels, including the novelisation of the games themselves.
 * Not to mention being used as an example of how to use Chapter Traits in the old 4th edition Codex (albeit with traits that were not at all representative of the Blood Ravens as seen in-game despite more fitting ones being available, making for a weirdly inverted case of Canon Defilement).
 * Elegant Nova of Progression first showed up in Keychain of Creation as an Alchemical Mad Scientist dedicated to making mortals into Alchemical Exalted piece-by-piece. Now, crack open Manual of Exalted Power: Alchemicals and flip through to "Notable Individuals"...
 * The Viashino of Magic: The Gathering were originally introduced in the Tie-in Novel The Prodigal Sorcerer by Mark Sumner. The designers of the game liked them so much that they worked them into the game, and they still turn up from time to time.
 * Gomorra, California, home of the tie-in Collectible Card Game, would eventually become an entire Immigrant Setting for Deadlands. Part and parcel to this were many, many Canon Immigrants, including most of the entire Whateley Family, Sioux Union, and piratical Maze Rats.
 * Many concepts devised for specialized settings in the D&D game have subsequently become incorporated into the core rule system, as when domains and darklords from the 2nd edition Ravenloft setting became a standard feature of the 4th edition Shadowfell.

Theatre

 * After a PC game was made out of Jeff Waynes Musical Version of the War of The Worlds, he utilised several features from it for the live stage version (most notably a large part of the Martian intro movie, and the game's model for the Martian flying machine which can be seen briefly during The Red Weed)

Toys

 * The Starlight Girls (the foster girls Jerrica takes care of) were created specifically for the Jem TV series. However, at least three of them: Ashley, Ba Nee, and Krissie, were later made into dolls.

Video Games

 * Karin Kanzuki, Sakura Kasugano's Rich Bitch Ojou rival from Street Fighter Alpha 3, was originally created for a Sakura-centric tie-in manga, Sakura Ganbaru! by Masahiko Nakahira.
 * Gouken, Ryu and Ken's sensei, was originally a character in a Street Fighter II tie-in manga by Masaomi Kanzaki. The character was later adapted in the video games' canon in the first Street Fighter Alpha before making a full-fledge appearance as a fighter in Street Fighter IV.
 * Note, that's Gouken and not Sheng Long. (Although it should be further noted that Gouken has all of Sheng Long's supposed moves.)
 * "You must defeat me to stand a chance!"
 * There's also Evil Ryu (from Masahiko Nakahira's Street Fighter Alpha manga) and Shadaloo Cammy (who first appeared in the inter-company crossover game X-Men vs. Street Fighter). Aspects of Cammy's back-story from the Alpha series, such as her codename Killer Bee, were also based on elements that originally appeared in Masaomi Kanzaki's Cammy Gaiden manga.
 * Maki is a triple canon immigrant, being one of the many new characters introduced in Final Fight 2 (where she was a Distaff Counterpart/Suspiciously Similar Substitute of Guy from the previous game), only to be immediately forgotten. And then Masahiko Nakahira brought her back to the limelight in Sakura Ganbaru!, causing Capcom to suddenly remember her and putting her in Capcom vs. SNK 2 Mark of the Millennium before she was eventually featured in the portable versions of Street Fighter Alpha 3 along with Eagle and Yun.
 * Mecha Zangief first appeared in the Marvel vs. Capcom games as a secret character. In Super Street Fighter IV, he returns as an alternate skin for Zangief.
 * Ingrid started out as a character for the cancelled Capcom inter-series crossover game Capcom Fighting All-Stars. She'd, however, make the jump into its "spiritual successor" Capcom Fighting Evolution, and later ported into the GBA version of Street Fighter Alpha 3. It was later confirmed that Ingrid is indeed part of the Street Fighter license.
 * Several monsters from Super Mario Bros. 2, which was just a Dolled-Up Installment based on the game Doki Doki Panic, have gone on to be included in later Mario games. These include Shy Guys, Bob-Ombs, and Birdo, as well as a race of mice creatures similar to the boss Mouser.
 * The Koopa Bros. of Paper Mario fame originally appeared in the Japan-exclusive manga Super Mario-Kun.
 * Toad's voice in the later games sounds suspiciously like his voice from the Super Mario Bros Super Show.
 * Peach's hovering ability also comes from this game.
 * Luigi was portrayed as timid and easily frightened in comparison to Mario (and generally more of a dork) in the Super Mario Bros Super Show long before he was shown as such in the games.
 * The Koopalings in Super Mario Bros 3 were originally unnamed in Japan, but the English localization gave them names. These would eventually become their official Japanese names in Super Mario World.
 * Mario spinning Bowser around by his tail in Super Mario 64 originated in this Japanese furikake commercial from the '80s.
 * There are quite a few examples from the Mass Effect series:
 * Technically, even Captain Anderson and Saren are examples of this trope; they're the main characters of Mass Effect: Revelation, the prequel novel released before Mass Effect 1.
 * Jacob Taylor and Miranda Lawson first appeared as the protagonists of Mass Effect: Galaxy before becoming party members in Mass Effect 2. In Jacob's case, he's probably one of the few video game characters to go from being a Player Character in one game to just a party member in a later one. Miranda herself had another appearance in Mass Effect: Redemption before Mass Effect 2 came out.
 * The Illusive Man first appeared in the novel Mass Effect: Ascension, a year and a half before his main series debut in Mass Effect 2.
 * Feron, Liara's drell companion in the comic Mass Effect: Redemption, returns as a character in Mass Effect 2's "Lair of the Shadow Broker" DLC. In fact, the whole mission pretty much revolves around rescuing him from the Shadow Broker--the fact that at the end is kind of an unintentional consequence of the whole thing.
 * Kai Leng, Recurring Boss in Mass Effect 3, first appeared in the novels Mass Effect: Retribution and Mass Effect: Deception.
 * Dr. Eva Coré from Mass Effect 3 seems like an example of this at first--Eva Coré is one of Jack Harper's (aka ) companions in the comic book Mass Effect: Evolution, which takes place 20 years before the series proper.
 * Kahlee Sanders was a main character in all four Mass Effect novels (Revelation, Ascension, Retribution, and Deception) before becoming a minor NPC in Mass Effect 3.
 * From Mortal Kombat, the character Quan Chi apeared first in the Animated Adaptation to later make his game debut in Mortal Kombat 4. Additionally, the concept of "Order vs. Chaos" was first used in the Comic Book Adaptation, years before the inclusion of the Order and Chaos Realms and its representative characters in Deception.
 * Puyo Puyo Fever was supposedly going to take place in an entirely different universe from the previous games...but lo and behold, Arle, the protagonist of the old Puyo games somehow found her way here, as did other classic Puyo characters in the sequel, putting them in the same continuity.
 * Silent Hill Homecoming, the latest installment in the Silent Hill series, does this with the art style, architecture, and specific locations from the non-canonical Silent Hill movie.
 * In Sonic the Hedgehog, Amy Rose and Charmy Bee are both canon immigrants. Both first appeared in a comic series in Shogaku Yonensei, published in Japan in 1992. While elements such as Nikki transforming into Sonic and being bullied by a lizard called Anton were left firmly in the comic, Amy (Nikki's girlfriend in the comics, ironically) was picked up and debuted officially in Sonic the Hedgehog CD (also ironic in the fact that she was labeled Princess Sally in the American manual anyway), while Charmy (one of Nikki's friends) was used as one of the characters in Knuckles Chaotix (even more irony in the fact that Sonic didn't have any appearance in that game aside from appearing in the good ending credits, thus didn't interact with him). Their backgrounds were, naturally, radically altered as a result.
 * In the Sonic the Hedgehog television series, there were robot characters called SWATbots. These robots were added into the recent Sonic RPG, Sonic Chronicles: The Dark Brotherhood, as a reference.
 * Likewise in Sonic Chronicles, Procurator Shade and the Nocturnus Tribe Echidnas share everything except their names with Julie-Su and the Dark Legion from the American Archie Sonic comics continuity - making them canon immigrants under false passports.
 * Not surprising, since rumor has it Sega gave Bioware the comics to read, when they asked for info on Knuckles' backstory.
 * In recent games, like Sonic Unleashed and Sonic and the Black Knight, Sonic can be seen eating chili dogs, something Sega picked up from the 90's cartoons. In Unleashed, eating chili dogs will actually give you some XP.
 * Arguably, the concept of Eggman and robotic buddies that's happened in at least two adaptations, has made it into recent games with Cubot and Orbot.
 * All that's missing is the tertiary robot with an odd job (Coconuts the janitor and Bokkun the messenger filled this position in the aforementioned respective adaptations).
 * Originally, Nasuverse Word of God stated that it was extremely improbable for two people with the Mystic Eyes of Death Perception; hence Shiki Ryogi and Shiki Tohno had to exist in a separate Alternate Continuity. However, Shiki Ryogi has just been announced as being in Melty Blood. In this case though, the immigration is quite literal.
 * Also, Kanshou and Bakuya Overedge form from the Fate/stay night anime became a canon.
 * The Resident Evil series features a machine known as The Red Queen, an Umbrella supercomputer dedicated to managing the company's assets. The Red Queen however is a canon immigrant from the non-canonical movies based off of the games, although in the movie, it is a hologram rather than super computer and has a distinctly more adult voice in The Umbrella Chronicles.
 * It was supercomputer in the movie, too; the hologram was just its visual representation in a bit of ill-advised Rule of Cool.
 * Resident Evil 4 also lifted the laser room of death from the movie. Albeit, it's beatable in the game for some odd reason...
 * The Chris and Leon seen Resident Evil 6 take the likeness of their counterparts in Resident Evil: Afterlife and Resident Evil: Retribution
 * Similarly, the transformation effect in the film Silent Hill was used for subsequent games in the series.
 * The Super Robot Wars series is loaded with these, ranging from the Mazinkaiser in F Final to the Great Zeorymer in Super Robot Wars Judgment and the Final Dancougar in Super Robot Wars Alpha 3 (the latter two having only existed on concept/paper prior to the games). Then there's whole stitch about Elzam von Branstein and Ratsel Feinschmeker: Elzam was introduced in Super Robot Wars Original Generation, but he appears in Alpha 2 as Ratsel, then subsequently back as Ratsel in the sequel Original Generation 2, where he gets his Ace Custom Aussenseiter, which then reappears in the last Alpha game. Of note is that Elzam was loosely mentioned first in the obscure Super Robot Spirits and in the back-story of Alpha. It isn't until Original Generation that he appeared in full.
 * While the appearances of Monolith Soft's Namco X Capcom Original Generation in Super Robot Wars OG Saga: Endless Frontier came off as a simple guest starring, their reappearance in the sequel Endless Frontier EXCEED may very well serve as the continuation of their story, suggesting that Monolith is willing to transfer their characters into the Super Robot Wars series in order to keep using them.
 * A few characters from the Pokémon anime cameoed in the Yellow version, notably Team Rocket's Jessie and James (who show up to fight you a few times). There's also a few references to anime counterparts (like Brock saying he wants to be a breeder, which seems to also be the case in HGSS making this a full-fledged Canon Immigrant).
 * There is also, to a lesser extent, the Nurse Joy model. Though the games do not call the nurses Nurse Joy and the nurses originally had blue hair, from Yellow Version onward the nurses resemble Joys more and more.
 * A gameplay immigrant was the "dash button", it originally debuted in the second game adaptation of the trading card game before moving over to the third generation, and has been in the main games since.
 * In Pokémon Pinball, Ecruteak and Cianwood City's music from Pokémon GSC was originally the Blue Field theme. Plus, the "Catch 'Em" theme in said field was originally the 1st Japanese opening theme, "Aim to Be a Pokémon Master".
 * The font used in the American logo would eventually be used for the Japanese box art for Poke Park Wii and its sequel.
 * Most of Pac-Man's supporting cast -- Ms. Pac-Man, Pac-Man Jr., Baby Pac-Man, and Professor Pac-Man -- were all originally from unauthorized Midway sequels to the arcade game.
 * Originally in Kirby, Meta Knight's two sidekicks were Meta Axe and Meta Mace, but in the anime Meta Knight is assisted by Sword and Blade Knight. Likely because of this, in Kirby Super Star Ultra, Meta Knight has Sword and Blade as helpers when playable. It helps that Blade Knight is already a helper.
 * The design of King Dedede's castle from the anime series was used in Squeak Squad and Epic Yarn.
 * Likewise, the Battleship Halberd's design from the anime appeared in Squeak Squad, then Super Smash Bros. Brawl came out and the Halberd's design from that game was used instead in Super Star Ultra and Epic Yarn.
 * The water ability from the anime will also appear in Kirby's Return to Dream Land.
 * Also, Kirby started saying "Poyo" in the anime, this has been transferred into Epic Yarn, Return to Dream Land, Mass Attack and Brawl's Subspace Emissary mode.
 * A good amount of anime characters make their first game appearances in Mass Attack's mini-games, including (but not limited to) Escargoon, Customer Service, Max Flexer, and Chef Shiitake.
 * The spear-carrying Waddle Dees from the anime show up in later Kirby games.
 * In some later games, Meta Knight wraps his cape around himself when he's not using it, a nod to the anime.
 * The GBA port of the first Breath of Fire gives names to three nameless Guest Star Party Members, with two of them (Sieg and Rai) taken straight from an early manga adaptation of the game, Princess of The Wings.
 * In Dead Space, the Divet Autopistol from the first game is revealed to have been left behind by the characters in its prequel sequel.
 * Konami decided to link their popular Castlevania series to the famous Bram Stoker novel Dracula, so when they designed Castlevania Bloodlines, instead of starring a Belmont, it featured a member of a related branch family who had emigrated to America -- the Morrises. John Morris (the member in question) is the son of the novel's Quincey Morris.
 * In the F.E.A.R. series, Michael Becket first appeared in Perseus Mandate, which is not part of Monolith's canon, but became the main character of Project Origin.
 * Unintentional, but Lamp Oil, which first appears as an item in both "Link: The Faces of Evil" and "Zelda: The Wand of Gamelon" becomes a real Zelda item in The Legend of Zelda Twilight Princess.
 * Quite a few things that have originated in Super Smash Bros. have found their way into its originating franchises:
 * Captain Falcon's Falcon Punch makes an appearance in the F-Zero: GP Legend anime.
 * The Green Missile and the Egg Roll are both utilized by Luigi and Yoshi in later Mario sports games. Peach using her hips as an offense in Mario Kart Double Dash may also qualify. The Whirling Fortress was also never used by Bowser before Melee, whereas he does similar moves rather often now.
 * Metroid Prime was the first Metroid game to include homing missiles, a year after Samus used them in Melee.
 * Kirby actually fought Master Hand and Crazy Hand in Kirby and the Amazing Mirror. Inhaling them gave him a reduced version of his Melee moveset.
 * Dedede's Jet Hammer may have been the inspiration for his tricked-out mallet in The Revenge of the King in Kirby Super Star Ultra. Also some shots of the Halberd in cutscenes in Ultra were re-used from Brawl's version of it as a stage.
 * Kid Icarus: Uprising features the re-imagined versions of Pit and Palutena that debuted in Brawl.
 * The American Commercial for the first Golden Sun game infamously had absolutely nothing to do with the game itself, save for featuring fantastic elements. It involves an opera house's pit orchestra fighting off a horde of gargoyles, and then taking down a dragon that took the form of a chandelier. Very cool, but it had nothing to do with the actual game. And then Golden Sun: Dark Dawn came around, and introduced a new summon named Crystallux. According to the legend, he was a dragon that so loved the music in the Belinsk opera house that he turned himself into a chandelier, so that he could live in the opera house and hear the music whenever he wished. Yes. It's the exact same dragon. He even tries to help you fight off some particularly nasty monsters when the opera house gets attacked. Thankfully, he doesn't get killed like he does in the commercial.
 * Although the summon sequence begins with him rising from the shards he was left in from the commercial.
 * The woman that dies defending the dragon from the monsters resembles the woman in the commercial.
 * Epona the horse, from the later games in the Zelda series, may qualify as this. Quite a few years before she made her series debut in The Legend of Zelda Ocarina of Time, Link had a similarly-colored horse named Catherine in both the cartoon and the comic book adaptation, both of which were based on the first two games in the series.
 * Spryte from the cartoon may very well have been an inspiration for Navi in Ocarina of Time, too.
 * Pitfall II: The Lost Caverns features Pitfall Harry's niece Rhonda, and their cowardly pet mountain lion Quickclaw, who were both originally created for animated segments from Saturday Supercade.
 * Although it took until the end of the trilogy, Gears of War 3 brings in a large selection of characters from the Expanded Universe, such Jace Stratton, Samantha Bryne and Bernadette Mataki into the playable campaign. All of them previously existed in the comics and novelizations. In a variation, Michael Barrack, who first appeared and was  in the novels, will be available as future Downloadable Content. Surprisingly, Alex Brand from the graphic novels has no planned appearance, much to some fans' disappointment.
 * In Donkey Kong 64, the Crystal Coconuts and the concept of Cranky Kong as a combination magician and Mad Scientist who made magical potions both came from the animated series of Donkey Kong Country.
 * In the Halo series, Dr. Catherine Halsey, who is an important supporting character in Halo: Reach, had already been playing a major role in the Expanded Universe since her debut in the 2001 novel The Fall of Reach.
 * Several other major EU elements introduced in The Fall of Reach have made their way into the games, including: Orbital Drop Shock Troopers (ODSTs), who first show up in Halo 2 and would eventually star in their own game; The Office of Navel Intelligence (ONI), which got a one-line reference in Halo 3 before playing a more important role in the plots of ODST and Reach; and Engineers, who first show up in Halo Wars, but got a starring role (and redesign) in ODST.
 * The SPARTAN-III program was introduced in the novel Ghosts of Onyx, which was published about a year before the release of Halo 3. In Reach, all but one member of Noble Team, including the player character, are SPARTAN-IIIs.
 * It's fairly safe to say that any character/organization/vehicle/etc. that is introduced in the expanded universe has a fairly good chance making it into the games; even the ones who don't show up or get a mention in-game will often get a nod in the promotional material.
 * Howard Blackwood, a character from the comic Silent Hill: Past Life appears in Silent Hill: Downpour.

Web Comics

 * In Something Positive, Fluffmodius, the "little blue freak" that yells "HELLO NEW FRIEND"! at Kharisma, was originally a one-off joke for his non-continuity strips for Rhymes With Witch. Let that be a lesson to you: Do not taunt the Word of God.
 * ...and going the other way, Rippy the Razor was a one-off gag in Something Positive, but now is Randy's tormentor in some RWW material.
 * The Dini-verse characters Kathy Duquesne, Roxanne Ballentine, and Sonia Alcana from the DC Animated Batwoman movie are regular characters on DC Nation, having been recruited by Hawkman to police his town between incarnations.
 * Somewhere askance of canonical Problem Sleuth, the Midnight Crew, a four-man mercenary group, was created as a donation request that spent most of their time fighting the protagonists. In Homestuck they are exiles in the Trolls' session, and were given about a month of screentime and character development. Later, in the Kids' session, they are given new names, and the leader ascends to Big Bad status.
 * Season 4 of Survivor Fan Characters pitted ten canon characters, such as Sephiroth, Riku, Shiki, and Minerva Mink against ten fan-made characters. On a more general note, in other seasons, characters from the fan-characters canon universes visit on the family and friend reward challenge, and on an even broader note, the host of all eight seasons so far has been Jeff Probst.

Web Original

 * Yelizaveta 'Bounce' from Survival of the Fittest version four started off as a character in the 'In-Universe Chat' (a chatroom where SOTF members could RP being members of the show's audience). After some time, she was brought into the version four pregame as a fully-fledged character.
 * Lastie's PRIMARCHS has Farseer Kyli, a character who was originally created to MST the story. Lastie featured her in the story's 3rd arc.

Western Animation

 * Woody Woodpecker has two: His niece and nephew Knothead and Splinter originally appeared in the comics, but were eventually brought over into his theatrical toons.
 * Disney's Max Goof was imported into the Disney canon from Goof Troop. This is unique in that Max has no "iconic" depiction to revert to and, unlike other characters, has aged appreciably over time. However, Max's appearance and role is arguably based on Goofy Jr., a character used in Goofy's original cartoon shorts (he once introduced himself as "Goofy Jr., ma'am").
 * In the Tom and Jerry cartoons, the grey mouse who could speak came from the licensed comics. There, he was called Tuffy, and was Jerry's friend; when he was adapted, he became Nibbles, and Jerry's nephew.
 * Lola Bunny. Created for Space Jam, she became a regular in Baby Looney Tunes, the comic series, and most recently The Looney Tunes Show.
 * Before Lola, there was Honey Bunny, Bug's girlfriend in the comics, who made a cameo appearance in the TV special "Bug's Bunny's Thanksgiving Diet".
 * The character Oil Slick was originally a toy-only character in the Transformers Animated series. However, the writers found the idea of a chemical warfare expert who turned into a motorbike with a ram's head on (and a Ninja to boot) the front rather appealing, and he was later written into both the supplementary comic series and given a cameo on the show itself as part of Team Chaar.
 * In turn, Animated bounty hunter Lockdown was eventually adapted into the G1 corner of the multiverse in one of IDW's comic books.
 * In fact, he did so by way of the Revenge of the Fallen toyline (that is, he was adapted to movie-style in that line, whose design was then used for him in a comic in G1 continuity), and what's more, they've done similarly for Lugnut since then; he got a toy in the Reveal the Shield sub-line, whose design then appeared in the Rodimus vs. Cyclonus comic, set during the events of the animated movie.
 * In addition, Blackarachnia made the jump from Beast Wars to Transformers Animated, and Bulkhead from Transformers Animated is now a core cast member of Transformers Prime.
 * Though The Goliath Chronicles has been excised from Gargoyles canon, with the exception of season premiere "The Journey", another part of the series has managed to find its way into fanon and eventually canon: The scene where Hudson's blind Human friend Robbins reveals that he already figured out Hudson was a Gargoyle, particularly the part where he mentions a scent "like old leather and concrete".
 * While the comic licensed by Marvel was deemed noncanon, Petros Xanatos appeared in #7 prior to his onscreen appearance in Vows.
 * Arguably Disney's best example; while Donald and Daisy Duck premiered in Disney animated shorts, one of Duckburg's most illustrious citizens, Scrooge McDuck, started as a supporting character in the Carl Barks' Donald Duck comics in 1947, where he grew in popularity unti he wound up getting his own title in the fifties. His first animated appearance was in an educational short called "Scrooge McDuck and Money" in 1967, and then he starred in the 1983 theatrical featurette Mickey's Christmas Carol, as Ebenezer Scrooge, of course. He then co-starred with Goofy in "Sport Goofy in Soccermania" before starring in DuckTales, cementing his place as one of the most famous cartoon ducks of all time.
 * Meanwhile, Donald's nephews, Huey, Dewey, and Louie, first showed up in the Silly Symphonies comic strip (which Donald starred in at the time). Their first appearance was later adapted into an animated short, and the rest is history.
 * Matilda and Sergeant Slipper were created for the animated adaptation of Dennis the Menace UK. They both made appearances later in The Beano.
 * A few elements of the 4Kids Teenage Mutant Ninja Turtles 2003 have made their way into the original comic book universe, including the Battle Nexus, and its proctor, the Gyoji; and more recently, Hun and (off-panel only, due to the series' cancellation) Agent Bishop.
 * On The Fairly Odd Parents, two of the Crimson Chin's villains, the Iron Lung and the Brass Knuckles, appeared in the non canon webtoons before appearing in the series proper.
 * The Animated Adaptation of Anne of Green Gables features the characters of Felicity, Felix, & Hetty King as well as suspected witch Peg Bowen, all of whom originally appeared in the live-action series Road to Avonlea (known just as "Avonlea" when it aired in the US on Disney Channel).
 * Milhouse on The Simpsons made his first appearance in a Simpsons Butterfinger commercial according to creator Matt Groening.
 * The character of Brutus from Popeye is an odd twist on the trope. The original Thimble Theater Newspaper Comics used the character Bluto first. After a two week fight with Popeye in the comics, Fleischer Studios thought he would be a good character to include in their theatrical cartoon shorts. Thinking (mistakenly) that Bluto was a creation of Fleischer Studios, Segar created a Captain Ersatz of his own character, named Brutus. Later in the Hanna-Barbara cartoons, Bluto was replaced with Brutus, the canon immigrant from the comics, who looked identical but had a different name, thus confusing children everywhere.
 * The antagonists from both live action Ben 10 films have appeared in Ben 10: Ultimate Alien. In that sense, Nanomech is one too.

Real Life

 * Audio-animatronic figures of Jack Sparrow and Captain Barbossa have been added to the Disney Theme Parks ride that inspired their movie franchise. An odd case, since the original version of the ride didn't have any story, as such.
 * Some say that the plot of the movie was partially based on a canceled Monkey Island movie, which was in turn based on a game inspired by the Pirates of the Caribbean ride.
 * Actually, it gets deeper than that and much more complicated. Monkey Island was visually inspired by the Pirates of the Caribbean ride, but the atmosphere and story elements were inspired by the novel On Stranger Tides. The Pirates of the Caribbean movies have a great deal that seems to have been lifted straight out of On Stranger Tides, as well. Now that On Stranger Tides is a Pirates of the Caribbean movie we've in some strange way come full circle.
 * When NASA opened a poll to name the new ISS module, Stephen Colbert rallied his fans cast write-in votes for "Cobert." After the poll closed (and "Cobert" had won by a large margin) NASA declined to use the name, opting for Tranquility instead. A few months later NASA installed the Combined Operational Load Bearing External Resistance Treadmill (COLBERT) as a nod to the contest winner, complete with mission patch.