"There is a house above the world, where the over-people gather.
Composed (usually) of the heavy hitters of The DCU, the Justice League has been around in one form or another since The Silver Age of Comic Books, and doesn't show any sign of going away. The team debuted in The Brave and the Bold #28 (February-March, 1960), created by writer Gardner Fox and artist Mike Sekowsky. Their appearances in three consecutive issues of Brave and the Bold served as a trial run. The concept sold well and the team graduated to its first eponymous title by October, 1960.
The original lineup is Superman, Batman, Wonder Woman, Green Lantern, the Flash, Aquaman, and the Martian Manhunter (commonly known as the "Magnificent Seven" or just the "big seven", and considered the greatest heroes on Earth by pretty much the entire superhero community). Which almost immediately (6 issues later) started to gradually expand to include Green Arrow, The Atom, Hawkman, Black Canary, The Phantom Stranger, Elongated Man, Red Tornado, Hawkgirl, Zatanna and, finally, Firestorm. After that, the group has repeatedly disassembled and reassembled, sometimes with drastic membership changes, including a revival of the original seven. Basically, every DC Comics superhero who didn't belong to another team (and a few who did) was a member at one time or another (and even an entire team of non-DC superheroes!). And as the premier group of heroes in the DCU, when a cosmic crisis threatens, every superhero available becomes a temporary member of the JLA, such is the importance of the group.
After Mark Waid and Grant Morrison's revival, the originals are considered the "Big Seven", and cover the archetypes any superhero team should possess (straight superhero, vigilante, magical being, speedster, underwater hero, cosmic hero, psychic).
Originally, they were the local crime-fighting club, composed of the best of the best. They were effectively a "social club" for superheroes, where they could hang out with similar people (when not fighting evil). There was no set leader, though certain heroes (such as Superman, Batman or the Martian Manhunter) often ended up taking leadership roles due to their popularity and skill. New members were chosen by voting, which might explain why several heroes that felt rather redundant were added to the roster. They had a series of special bases over the years, most notably a satellite headquarters in orbit above the Earth.
In the 80's, DC's editorial team noticed that they were being outsold by the Teen Titans and the X-Men, more action-oriented, character-driven teams. So, suddenly, Aquaman gave a big speech about how the team couldn't depend on heroes who were too busy to show up all the time, and reformed the team with a bunch of second-stringers and a few new characters. They operated out of a warehouse in Detroit (for which they got the Fan Nickname "Justice League Detroit"). For this reason they were a little ineffectual during Crisis on Infinite Earths.
As a result of this, the team was retooled again in the '80s, becoming Justice League International (taking over the Global Guardians' role, and adding in some of the latter group's members) which then split into Justice League America and Justice League Europe, which later (after their membership grew huge) further split into the Justice League Task Force (a "superhero school" led by the Martian Manhunter), and Extreme Justice, which was led by the more proactive Captain Atom.
This approach fizzled after a few years, so DC took the team back to basics by reuniting the original Big Seven and giving them a lunar Watchtower base. The series was relaunched as JLA by Grant Morrison, who emphasized the team's role as the "gods" of the DCU, and had them only go up against the sort of tremendous, cosmic-level threats which befitted that stature. This new approach was such a hit that for several years pretty much all major events in the DCU revolved around the League, and countless miniseries and one-shots were spun off the new title. After Morrison left, succeeding writers (most notably Mark Waid) continued his approach.
The team has a long tradition of Crossovers with the Justice Society of America. Once labelled "Crisis on (Something)" fairly often; commonly takes place at a Christmas/Thanksgiving dinner attended by both teams, when suddenly a villain attacks. This stopped happening regularly around 1986 with Crisis on Infinite Earths, though the tradition has popped up sporadically since then (1998's "Crisis Times Five", 2002's JSA/JLA: Virtue and Vice, 2007's "The Lightning Saga").
Here are the different incarnations of the Justice League of America so far:
- The Original Big Seven (Gardner Fox/Mike Sekowsky): Superman, Batman, Wonder Woman, the Flash II (Barry Allen), Green Lantern II (Hal Jordan), Aquaman & Martian Manhunter, based inside a hollow mountain, the "Secret Sanctuary." Later members included Green Arrow, The Atom II (Ray Palmer), Black Canary II and Hawkman. Snapper Carr served as the team mascot, or as The Scrappy, depending on who you ask.
- The Post-Crisis/Year One League (Mark Waid): Like most things in the DCU, this was retconned after Crisis on Infinite Earths. In this version of the team's history, Superman, Batman and Wonder Woman were no longer founding members of the League, but Black Canary II was. Following the events of Infinite Crisis, Superman, Batman, and Wonder Woman were restored as founding members; it's not entirely clear whether Black Canary remains as an eighth founder, or joined later as she did in the original continuity.
- The Satellite-Era League: Basically everyone mentioned above plus Elongated Man, Hawkgirl I, Firestorm I (Ronnie Raymond/Martin Stein), Red Tornado II, and Zatanna. Also Elongated Man's wife, Sue Dibny, sort of. The Martian Manhunter was absent for most of this era when it was originally printed, but seems to have been retconned back in. Also had stretches where Green Arrow and/or Batman had quit the team, but overall, the lineup was quite stable by today's standards. There were several honorary members of whom only one - The Phantom Stranger - actively participated in their cases on a semi-regular basis.
- Justice League Detroit (Gerry Conway): Four established JLAers (Aquaman, Martian Manhunter, Elongated Man, and Zatanna), one previously-obscure character (Vixen), and three complete newcomers (Vibe, Gypsy, and Steel II - a Legacy Character of Commander Steel, not to be confused with John Henry Irons). Later on, Aquaman quit and Batman rejoined. Has its fans, but widely considered a Dork Age.
- Justice League\Justice League International (Keith Giffen/J.M. DeMatteis): Created after the events of the Legends Crisis Crossover. Officially, started with a (probably editorially mandated) lineup of Batman, Martian Manhunter, Green Lantern III (Guy Gardner), Black Canary II, Captain Marvel, Dr. Light III (Kimiyo Hoshi), Blue Beetle II (Ted Kord), Mr. Miracle (with his 'manager', Oberon), and Doctor Fate II, a lineup that showed off the possibilities of the new continuity by featuring characters previously from four different Earths. The writers had different ideas; Doctor Light never actually joined (until much later) and Doctor Fate and Captain Marvel were gone within six issues, and the stories soon took on a generally humorous tone that did not, at first, sit well with some fans. Booster Gold, Captain Atom, Rocket Red #7 (Vladimir Mikoyan), Fire, and Ice were among the first of many to join as those same elements of humor quickly made the series a fan favorite. After the events of Invasion!, as well as the opening of Justice League Europe (see below), JLI was renamed "Justice League America" (no "of"). After Giffen and DeMatteis left the series following the "Breakdowns" arc, the series struggled along as writers such as Dan Jurgens, Dan Vado, and Gerard Jones tried to keep the book and its spin-offs afloat with little success.
- Justice League Europe (Keith Giffen/J.M. DeMatteis): The Flash III (Wally West), Captain Atom, Rocket Red #4 (Dmitri Pushkin), Power Girl, Elongated Man, and Metamorpho (and Wonder Woman, who left after the first mission). Created after the Invasion! crossover. Subsequently joined by Crimson Fox, Green Lantern II (Hal Jordan), Dr. Light III (Kimiyo Hoshi) and Aquaman. Later renamed Justice League International, just to be confusing.
- Justice League Task Force (David Michelinie/Sal Velluto) Originally a rotating membership of whoever would be needed for a given mission. After Zero Hour, reinvented as the League "school" with the Martian Manhunter, the Ray, Triumph, Gypsy, and L-Ron in the body of Despero.
- The Justice League International was reformed in the 2010 bi-weekly series Justice League: Generation Lost in order to track down Max Lord. This version of the team featured Booster Gold (as team leader), Captain Atom, Fire, Ice, Blue Beetle III (Jaime Reyes), and a brand new Rocket Red (Gavril Ivanovich).
- The Post-Zero Hour League (Gerard Jones): Wonder Woman, the Flash III (Wally West), Hawkman III (Katar Hol ... sort of), Fire, Icemaiden (Sigrid Nansen), Nuklon, Obsidian, Blue Devil. The most radical reinvention of the Giffen/DeMatteis League, Zero Hour had all the teams disbanded, and Wonder Woman reinvent the League as a "superhero club", with an official membership of "anyone who's interested". Captain Atom decided the real Justice League ought to be better organized, but should have been careful what he wished for, because the result was...
- Extreme Justice (Dan Vado/Marc Campos): Captain Atom, Firestorm (Ronnie Raymond), Booster Gold, Blue Beetle II, Amazing Man II, Maxima. As if the "Extreme" in the name wasn't clue enough, this series was a massive Dork Age, with art and page layouts that severely aped the worst of Rob Liefeld and Jim Lee's tendencies (overly muscular, unexpressive characters and "flip the comic sideways" pages) with a heavy emphasis on action over character dynamics.
- JLA (Grant Morrison/Howard Porter/Mark Waid/Joe Kelly/Doug Mahnke): Superman, Batman, Wonder Woman, the Flash III (Wally West), Green Lantern V (Kyle Rayner), Aquaman, Martian Manhunter. In other words, the original seven (or rather, five of them and the then-current successors of the other two). Based on the Moon. Later included Steel III, Plastic Man, Oracle, Big Barda, Orion, Zauriel, Huntress, and, temporarily, Wonder Woman's mother Hippolyta instead of Diana. Main focus was the core seven (occasionally plus Plastic Man), though. Largely had to do with the idea that because the JLA is so powerful, they should be fighting harder villains than just super-terrorists. Very fondly remembered, even by those who hate everything else Grant Morrison has ever done.
- The Post-Infinite Crisis League (Brad Meltzer/Ed Benes/Dwayne McDuffie): Varied but seemed similar to the Satellite version, except they were now based in the Hall Of Justice. Started out with Superman, Batman, Wonder Woman, Green Lantern II / IV (either Hal or John Stewart), Vixen, Black Canary II, Red Tornado II, Black Lightning, Red Arrow, and Hawkgirl; Geo-Force was often pictured as part of this lineup, but he never actually joined, he just played a minor part in their first story arc.
- The Post-Final Crisis League (James Robinson/Mark Bagley): Spinning out of Robinson's Justice League: Cry for Justice miniseries, the new team comprised Green Lantern II (Hal Jordan), the Atom II (Ray Palmer), Batman III (Dick Grayson), Mon-El, Donna Troy, Cyborg I, Doctor Light III, Starfire, Congorilla, and the Guardian. Green Arrow, the main character in Cry For Justice, was a member for the first few issues, until certain events in Cry For Justice caught up with him.
- The Post-Blackest Night League (James Robinson/Mark Bagley): According to a recent convention appearance, Robinson wasn't satisfied with the way his JLA was going; among other things he thought he had tried to put in too many characters. Starting recently, it's now Batman III (Dick Grayson), Supergirl, Donna Troy, Jade, Starman (Mikaal Thomas), Congorilla and Jesse Quick, thus making a somewhat rough second generation equivalent to the original team lineup.
- The New 52 League: This team is written by Geoff Johns and features the Big Seven, only with Cyborg replacing Martian Manhunter (who is in Stormwatch instead); in addition to these seven, a leaked image suggests Green Arrow, Hawkman, the Atom IV (Ryan Choi), Firestorm I, Mera, Deadman, recently introduced character Element Woman, and reimagined Golden Age heroine Lady Luck as additional members.
- In addition, there is a new, separate Justice League International, written by Dan Jurgens, with Booster Gold as the team leader, Batman (Bruce Wayne), Green Lantern III (Guy Gardner), Fire, Ice, Vixen, Rocket Red, Lady Godiva, and August General In Iron (a Chinese hero introduced in 52).
- There's also the Justice League Dark, written by Peter Milligan, a team of supernatural heroes featuring John Constantine, Deadman, Madame Xanadu, Zatanna, and Shade the Changing Man.
DC even has a Funny Animal counterpart of the Justice League: the "Just'a Lotta Animals" of Earth-C-Minus, a parallel Earth that's a funny-animal counterpart of the mainstream DCU. The core roster of the "JLA" consists of:
- Super-Squirrel (a squirrel, counterpart of Superman)
- The Batmouse (a mouse, counterpart of Batman)
- Wonder Wabbit (a rabbit, counterpart of Wonder Woman)
- Green Lambkin (a male sheep, counterpart of the Silver Age Green Lantern)
- The Crash (a turtle, counterpart of the Silver Age Flash)
- Aquaduck (a duck, counterpart of Aquaman)
Other members included: Hawkmoose; Green Sparrow; Stacked Canary; the Martian Anteater; the Item (the Atom; an elephant); Zap-Panda (Zatanna); and Elongator (the Elongated Man; an alligator).
- Alternate Company Equivalent: The Avengers
- Animal-Themed Superbeing: Batman and Hawkman are the most prolific but we also have Hawkwoman, Animal Man, Vixen, Black Canary, and Red Robin.
- This is also prevelant in enemies they have fought: Black Manta, Gorilla Grodd, B'Wana Beast, Starro, etc.
- Badass Crew: THE most Badass Crew in the DC Universe.
- Crossover: The crossover with The Avengers is the most famous but the team has also crossed over with the X-Men during All Access', a sequel to Marvel Vs. DC. It also had a crossover with the Wild CATS before Wildstorm went to DC.
- I'm Crying but I Don't Know Why: In the Morrison run, after their attempt to conquer Earth fails when they are found vulnerable to fire, the fifty White Martians, face the Martian Manhunter. At the end, the narrator tell us of a man that, every morning just after awakening, feels like he had once incredible power that is forever lost. This feeling of loss and frustration is shared by other fifty humans scattered in the Earth, and is so big, he wants to cry. But he doesn’t, because he is an adult and has no time for such nonsense. So he smiles, goes out and begins his working day as a fireman.
- Loads and Loads of Characters: It would be more difficult to name DC superheroes who weren't members of one version of the Justice League or another.
- Spiritual Successor: Of the Justice Society of America.
- Starfish Alien: Starro is a Trope Codifier.
- West Coast Team: There was a Justice League International, a Justice League Europe, a Justice Black Ops group, and even an Antarctic League among many others (the page description has a fuller list).