Pop Culture Isolation

""The wall between us all must fall""

- Living Colour, Wall

""Why my buzz in L.A. ain't like it is in New York?""

- Jadakiss, Why

Pop Culture Isolation is basically a case of pop culture myopia of sorts. Where celebrity, music genres, media or events that are huge and significant in one subculture or ethnic group, but elsewhere nobody knows it exists or is indifferent to it altogether. We're not talking about separate countries here, but within the same country or region. A lot of this is especially prevalent in entertainment, especially music. Radio is probably the main cause of this as radio is very isolated in terms of programming and format. Though some just see all of this as another form of segregation.

Let's face it, there are cultural barriers, and people thrive in their own microcosm. Another likely reason for this is because mainstream media is so homogenized and is prone to favoring monochrome pop culture that other cultures start their own pop culture media outlets. That fuels this trope even further for better or for worse. This isolation of pop culture can lead to such ignorance as Did Not Do the Research or Cowboy Bebop at His Computer. It's even possible for this trope to happen within the same culture. This, in turn, resulted in a pop cultural Broken Base or Fandom Rivalry. Hip Hop is a good example of this (see Hip-Hop's Broken Base entry). This trope possibly could lead to Monochrome Casting.

Expecting Pop Culture Isolation not to be an issue is a sure way to incur Pop Cultural Osmosis Failure.

Contrast Small Reference Pools, and Popcultural Osmosis. May lead to Germans Love David Hasselhoff or Americans Hate Tingle. Could also overlap with Critical Dissonance. This trope along with Public Medium Ignorance goes together like peanut butter & jelly. This often is the cause of Minority Show Ghetto.

Anime & Manga

 * A good deal of Anime and Manga, outside Sailor Moon, Speed Racer and the like, is not well known outside the fanbase.
 * This even shows up within manga fandom itself. Creators like Naoki Urasawa and Fumi Yoshinaga (of Antique Bakery fame) have multiple series published in the US, constantly appear on "best of" lists, and have won tons of awards - yet are virtually unknown outside of the "grown-up comic fans" circle.

Comic Books

 * Superman, Batman, Wonder Woman, Spider-Man, the Fantastic Four, X-Men (at least Wolverine and possibly Cyclops), Aquaman, Iron Man, and The Incredible Hulk are the only superhero exceptions to this trope. Even then, the only of their supporting cast to be generally known by people are The Joker, Robin, Lois Lane, and possibly Lex Luthor and Catwoman. And even the above list may be a stretch. Would your grandmother recognize any of the above characters besides Superman, Batman, Wonder Woman, Robin, The Incredible Hulk, and Spider-Man?
 * Female and black superheroes are a big victim of this trope. Whenever a new (or newly popular) black or female character is mentioned in a news story (especially when the entire point of the story is that most superheroes are white men, such as when a paper interviews a local artist who's just getting into the industry, almost always involving a quote along the lines of "reading comics as a kid, I always wondered why there weren't more characters who looked like me") the article will act as if there are, at most, five black superheroes and no superheroines except Wonder Woman.
 * At least not any prominent ones, which is likely what they might be referring to. Outside of Storm and maybe Luke Cage there really isn't any. The rest are just window dressing. There's plenty of white female heroes though, and not just in the background.
 * There are more: John Stewart was the local Green Lantern of choice in the DCAU, which later featured Vixen as one of the main female heroes. Static Shock had his own TV series. Falcon as a member of the Avengers and Black Panther have been arguably more significant than Luke Cage.

Fan Fic

 * There's a whole subculture dedicated to this. But it's only popular with the geek side of the internet.

Film
""Either they don't know, don't show, or don't care about what's going on in the hood""
 * Boyz N the Hood: Which this trope was inversely Lampshaded in the film it self by the character Doughboy.


 * Lords Of Dogtown
 * Menace II Society
 * Fear of a Black Hat, contrasted with This Is Spinal Tap (which can also fit)
 * In an inversion, Australian film critic David Stratton seems to be quite isolated from other forms of media - in his review of The Simpsons Movie he said he had never watched The Simpsons, in his review of Bee Movie he admitted to never having watched Seinfeld, and he also said he had never read the book Where the Wild Things Are in his review of that movie.
 * Some critics and pundits would argue that such a stance is actually for the best, as it ensures that reviewers will remain unprejudiced toward the film content and avoid Hype Backlash and / or They Changed It, Now It Sucks. One theatre critic, for example, had never seen any incarnation of West Side Story prior to attending a recent Broadway revival of it; with this fresh and unjaded perspective, the reviewer was able to honestly (if kindly) evaluate the play's objective worth and point out any flaws it had. (After all, a worshipful attitude often indicates just as much bias as an unreasonably hateful one.)
 * The popularity of several cult actors, at most they'll likely just be Hey, It's That Guy!! But in certain circles they're as popular as Tom Cruise, and Will Smith. A few Examples are....
 * Bruce Campbell
 * Tony Todd
 * Michael Jai White
 * Tiffany Shepis
 * Julie Strain: Basically a female Bruce Campbell
 * Jeffrey Combs
 * Sybil Danning
 * Debbie Rochon
 * Summer Glau (arguably anyone who was in Firefly)
 * Asia Argento
 * Tom Savini
 * Beverly Lynne
 * Don Wilson
 * Christine Nguyen
 * Shannon Tweed
 * Kane Hodder
 * Misty Mundae
 * Lance Henriksen
 * Shannon Whirry
 * Brad Dourif
 * Also true about many African-American actors, such as Mo'Nique, Loretta Devine, Angela Bassett, Boris Kodjoe, Jill Scott, Tracee Ellis Ross, Meagan Good, the list goes on. Often when African-American actors have a movie that is a crossover hit, that movie will be treated as their first by mainstream media.
 * Hilariously demonstrated by Fox News when LL Cool J demanded to have a pre-recorded interview dropped out of a program hosted by Sarah Palin. In an apparent Take That, one of the network anchors, referencing his role in the popular NCIS: Los Angeles, probably the only time most of the Fox News main demographic would have ever seen him acting, said there was no hard feelings and wished him well "in his fledgling acting career". LL Cool J had, at that point, been acting in film and TV for nearly a quarter of a century.
 * In the days of drive-ins and regional film distributors, it was possible for a filmmaker to be successful making movies that did good business in one region of the United States, but were almost completely unknown elsewhere. The North Carolina-based Earl Owensby, aka "The Redneck Roger Corman," is but one example.
 * The financial success of Tyler Perry's movies, particularly Diary of a Mad Black Woman, seemed to catch the mainstream media off guard. Perry had been currying good favor with black audiences through his plays for the better part of a decade, but the white American majority was ignorant of his existence until Madea hit the mainstream.
 * The audience for Perry's films are usually black women, a demographic that is either virtually ignored by mainstream films or relegated to a supporting "sassy friend" sidekick for the star. The fact that black woman might want to watch movies where people who look like them want to find some fulfillment out of life besides following their white friends around and supporting them seems have found voice in Perry's works. YMMV as to whether or not he's good at this.

Folklore

 * Southern folklore probably counts, especially black southern folklore.
 * Conversely, any non-black Southern folklore—Cajun, white Louisiana Creole, or various Native American cultures, for instance—will frequently be assumed to be of black origin, even if it can be proved otherwise.
 * In one sense, however, it is probably impossible for this trope to exist in the realm of folklore because so many myths and legends are remarkably comparable across cultures.

Food

 * A lot of region-specific cuisines. Most of what we regard as "typical" American food (hamburgers, hot dogs, etc.) come from the upper Midwest, which is where most middle-class Americans have tended to live.
 * Certain soft drinks are only popular in certain regions:
 * Faygo and Vernors are mostly found in the Midwest.
 * Green River sodas are only found in the area around Chicago.
 * Grapico, a very popular grape soda is primarily found in Alabama and surrounding states.
 * Likewise with Buffalo Rock a VERY strong ginger ale that's considerably more popular than Canada Dry.
 * Nehi is typically limited to the South.
 * While popular in Mexico, Jarritos and Sangria Señorial are typically found only in the U.S. in areas with prominent Mexican population.
 * Briefly averted with Big Red, a Texas-based red cream soda that enjoyed a minor surge in popularity in other states during the first years of the 21st century.
 * RC Cola is available worldwide but is massively popular in the American South, where, paired with regional favorite snack food Moon Pies, formed the "working man's lunch."
 * SPAM (outside of Alaska and Hawaii) is only popular among blue collar and low income families.
 * Same could be said for things like Potted Meat, and Vienna Sausages.
 * Kool-Aid, similarly could be considered a blue-collar-specific beverage.
 * Which would be ironic, since it was first marketed to middle-class people.
 * Blue Moon ice cream is popular in the Great Lakes states (most notably Michigan and Wisconsin), but is virtually unknown anywhere else. This is complicated by the fact that what exactly Blue Moon tastes like is almost as unique as the vendor who sells it, with flavors ranging from almond to spices to cola (although ironically Word of God says "true" Blue Moon is NOT "tutti-frutti" or blue raspberry).
 * Caviar. Admit it: unless you were reared in an old-money family, you spent practically all of your childhood completely in the dark about what that was. (For the record, it's pickled sturgeon eggs from the Caucasus region of central Eurasia.)
 * Eagle Brand baby formula and dehydrated milk products are so ubiquitous on certain Southwestern US Indian reservations that they're mentioned by name in the phrasebook at the back of the best-selling Navajo dictionary. Probably nobody not from one of those Indian reservations, or near them, has even heard of it.

Literature

 * Zane novels, black erotic literature, probably count.
 * Young adult literature, obviously. Because these novels and short stories are read neither by single, middle-aged or elderly adults (unlike generally "serious" fiction, which is acknowledged by critics and the media) nor by young parents with prepubescent children (as is Dr. Seuss, etc.), they are relegated to the readership of adolescents and tweens, whom mainstream culture tends to ignore except as a marketing demographic (and today's businesspeople are not trying to sell a lot of books). Go ahead: ask your typical fiftysomething Baby Boomer who Wilson Rawls was; they probably won't remember, if they ever knew about him to begin with.
 * Same thing could be said for Speculative Fiction (Sci Fi, Fantasy, and Horror). This also swerve into Sci Fi Ghetto territory as well.
 * In-Universe example meets Truth in Television in Jorge Luis Borges short story  "Averroe's Search" : Averroes, a philosopher confined to the Islamic orb, never could understand the terms Tragedy and Comedy.

Live Action TV

 * The TV series The Game is one of the most, if not the most, popular drama/comedies in the black community. Most white people aren't even aware the show exists. The show is now on BET but even when it was on CW it never really found a strong white audience.
 * George Lopez and Chris Rock are interesting examples since before they had their own self titled sitcoms they were well known, but they weren't well liked by anyone outside of their targeted demographics.
 * Steve Harvey is a very popular black comedian in the black community, but not too many people outside of it even know he exists. He arguably may have overcome this due to his sitcom, and appearing in The Kings of Comedy. And taking over as the host of Family Feud in 2010.
 * This is arguably true of most Black comedians before they land a sitcom deal, or hell, any comedian since they tend to only be popular within a certain niche (women, college students, blacks, Latinos, Asians, other ethnicities, etc.)
 * The Cosby Show subverted this; on the other hand, it was Bill Cosby's intention.
 * Roseanne contrasted with The Cosby Show, Not in terms of race, but class. In fact, you could swap out Roseanne for Good Times and get the same results.
 * MTV was also the cause of a lot of this, so much so that MTV refused to acknowledge that 90% of the songs on the chart were by black singers and kept trying to push a next Big White Hope like Winger or Warrant. There was such an embarrassing disconnect between their Top 20 played videos and the Billboard charts back then. David Bowie awesomely called them out for it during a interview with the network. They eventually caved in with the meteoric rise of Michael Jackson though.
 * The Nineties version of MTV subverted this trope, though, by basically not putting music in a box or programming block (Yo! MTV Raps, 120 Minutes, and Headbanger's Ball being the exceptions). On the other hand, this might be why they started putting music in a programming block and eventually stopped showing vids all together circa the early 00's. Simply put, nobody was gonna wade through rap vids to see a rock vid or vice versa.
 * The popularity of Martin. VH-1's I Love the '90s actually brought up that the show was virtually unknown to white viewers, in part because it was scheduled against Seinfeld.
 * Similarly, Living Single contrasted with Friends, some even going as far as to say the latter ripped off the former or at least inspired by it.
 * According to VH-1 Classic, New Wave and Hair Metal were the only popular music genres in The Eighties. Care about college rock or old school hip hop? Hope you're willing to stay up until 3:30AM!
 * Doctor Who provides an age-gap version of this trope all by itself; there are passionate fans of the series who either had (or continue to have) no idea that there was a show before 2005 and / or have no interest in watching any of the old series.

Magazines

 * Rolling Stone and similar mags have been accused of having a rock bias.
 * RS in particular is accused of 60's-70's bias in their lists.
 * The Source magazine, or any genre specific mag is this by default.
 * Lowrider mags, vs custom car mags (like DUB magazine), sport tuner car mags, and American muscle car mags. There's over-lap but they're somewhat significantly separated. Plus each scene has its own car culture, and preference of female models. Mags like DUB almost always have black girls AND Hispanic females, whereas the lowrider mags are more or less exclusively Hispanic, the tuner mags are almost always southeast Asian, and the muscle car mags are almost always white.

Music

 * R&B of the '30s and '40s was generally known only to black people due to segregation, making this trope Older Than Television. This isolation was made clear by a name given to R&B back then--"race music."
 * Same happened to Jazz and Blues.
 * Also with rock and roll, where it originated.
 * Most pop-culture music trends start out this way. Punk rock (the American version, at least) started out in lower Manhattan sometime in the mid-Seventies and slowly gained a following in other big cities across the country before finally breaking through to the mainstream. Similarly, hip-hop began in the Bronx and only gradually spread throughout the rest of New York and then to Los Angeles before going nationwide.
 * The British parellel concerns a cultural establishment - including big radio and TV names - who are based in London, consider the London scene is all and everything (and dismiss the rest of the country as "provincial"). Therefore they fail to notice what's going on outside London and only register it either when it moves South or it gets too big to ignore. Examples: "Northern Soul", a specific sort of soul beat popular in Wigan and the North-West, so popular that people from all over came north to join in, but largely ignored by the establishment. Or the way northern groups wrre ignored - the myth grew that punk rock was solely a London creation and bands from other parts of the country were simply imitating. (as the British provinces are of course populated by people incapable of creativity.)
 * Grunge was very popular among young white youth. But young Blacks and Latinos for the most part was somewhat oblivious to it. The Lollapalooza tour helped bridged the gap a little.
 * The reason hip-hoppers were oblivious to the grunge movement was because Hip Hop was going through what some would call a Golden Age renaissance. Nostalgia Filter card aside, most believe 1994 alone crushes everything that came out in the past decade. Some argue that that era was a really, really good time period for Hip Hop and its fans. So basically Black/Latino youth were preoccupied by their own cultural rise.
 * The Mexican singer Selena might also count. How many of you knew of her before she died?
 * Some say this trope created rockism.
 * During the documentary Pump Up the Volume (a docu-series about the rise of House, techno and the whole Detroit/Chicago/New York scene.) One guy was discussing the backlash against Disco around that time. He said there was a bonfire where people were standing in a line throwing in disco records (Now if you're Genre Savvy enough you know where this is leading), similar to Chicago's Disco Demolition Night. He began to notice that most of what they were burning isn't disco, but just black music in general. said he saw one guy with a Marvin Gaye record in his hand. This is also a double example as around this time House was only thriving in Chicago, and the New York underground.
 * Many listeners dismissed disco as "too black" or "too gay," or both: making it the musical sub-genre equivalent of a Twofer Token Minority.
 * On a similar note how many urban black people can tell you the difference between Aerosmith and Alice in Chains. Keep in mind rock is almost non-existent on black radio, so the popularity of these bands probably flew over their heads (unless you include the general mainstream media which is biased toward rock anyway). Or how about the fact some blacks got into rock thanks to bands like Faith No More, and Living Colour during the late 80's, and Nu-metal during the late 90's and early zeros due to them incorporating Hip-Hop, Funk and rhythm, or soulful vocals in Corey Glover's case? There's also the fact that some suburban whites can't tell you the difference between Bone Thugs-n-Harmony and Run-DMC. To outsiders rap music might as well all be the same.
 * There's always a segment of Black people with a vested interest in rock music. From the fact that rock came from Black singers such as Chuck Berry. But not as much as say Hip Hop and R&B.
 * A funny sub example of this trope is that of singer Dionne Farris. Ask a white suburban person what song they know by her and they'll almost always say "I Know" (a Pop/Alt/rock song). Ask black urban music listeners and they'll say the song "Hopeless" (which is a down tempo soul song). The contrast is jarring, and funny.
 * Another example is modern radio. Which is heavily segre...uh...divided up.
 * A inverse hip-hop example (quoted above) is from the east coast rapper Jadakiss when he asks "Why my buzz in L.A. ain't like it is in New York?"
 * Hip-Hop somewhat had this bad. If you're not a hardcore meticulous Hip Hop connoisseur who actively seeks out artists on your own, you probably missed out on a lot of regional acts. As radio from each region had different and diverse play lists. So whomever was popular in in the Northeast might not be as popular in the Southwest. For better or for worse it's different now though, as most stations tend to follow a VERY strict playlist. And for the most part they're more or less the same around the country. Likely because most radio stations are corporate owned now instead of privately owned.
 * Queen Latifah said if it wasn't for rappers like N.W.A. she wouldn't have known what life was like in south central LA.
 * Go to a few rock concerts and you'll see a sprinkle of a few black kids, But not a lot.
 * In the documentary Afro Punk, some of the black kids that were interviewed said that they didn't always feel accepted. Or when they did get acceptance, it felt like it was for the wrong reasons to them.
 * When Eminem's third album The Eminem Show was released, two different singles were promoted at the same time on different genre stations. "White America" was mostly played on the rock stations, while "Cleaning out my Closet" was played on hip-hop stations.
 * TLC's Unpretty had 2 different versions released for radio. One was a "Urban" mix, and the other was a mix for pop radio. The latter was the original version though.
 * There's a lot of guitarists out there who are revered and recognized and put on a lot of top guitarists list. Guitarists like Steve Vai, Eddie Van Halen, etc. But you'll be hard pressed to see people like Vernon Reid, and Ernie Isley mentioned, or listed though. Exceptions being the politically correct choice of Jimi Hendrix, and MAYBE Eddie Hazel...maybe.
 * Clive Davis INTENTIONALLY invoked this when marketing Whitney Houston. Primarily by sending her exclusively to A/C radio stations instead of urban radio stations.
 * This might have been the seed that help formed "The Black Rock Coalition"
 * New Edition contrasted with New Kids on the Block, This is believed to be why the latter was created in the first place. Maurice Starr was apparently very Genre Savvy.
 * 3 Six Mafia Lampshade this with the album title "Most Known Unknowns"
 * This trope possibly explains the sub-culture division among 40 somethings when it comes to black music. In the beginning when hip-hop was in its infancy in the early eighties, only a hand full of 20-somethings were caught up in the culture of Hip Hop, while the majority of the other 20-somethings were still into the post-disco/R&B new wave funk scene. This explains the cultural schism of 40-something African Americans regarding the hip-hop culture, and why you have 40-something hip-hoppers and hip-hop artists, and 40-somethings who are outside the culture, despite being young adults around the genre's inception.
 * It can still be true today with R&B. Everybody knows Alicia Keys, Beyoncé, and Rihanna but very few people know India Arie, Maxwell, Musiq Soulchild etc. outside the African-American community.
 * Similar to the New Edition and New Kids On The Block example; There was Pat Boone who used Covered Up as a way to market black music to whites. But all it did was veer into Unfortunate Implications territory..
 * Robyn had a "urban mix" for Do You Really Want Me for urban radio stations. She also counts in another way in that some think she's a new artist, but she's been around since the late 90's. The aforementioned song being released in 1998.
 * Arcade Fire took home a Grammy for Best Album in 2011. They're not signed onto a major label, and apparently not known by a very large portion of the population, prompting various "WTF WHO ARE THESE GUYS AND WHY'D THEY TAKE GAGA'S BEST ALBUM AWARD?" Tweets and Facebook posts.
 * Chronicled in this Tumblr blog, with a heaping helping of Fan Dumb.
 * This is also the reason why many R&B/Pop artists usually have to release two singles at a time: one for pop radio and the other for the urban market.
 * Beyoncé basically had a Distinct Double Album (I Am...Sasha Fierce) for this - one side being the soft pop ballad and the other being urban jams. She released If I Were A Boy mainly for pop radio and Single Ladies for the urban market. The experiment Succeeded Too Well and the biggest hits from the album were only the urban songs.
 * Chris Brown is balancing his F.A.M.E. album to have pop and urban singles and released the poppy Yeah 3x to pop radio to compliment Deuces.
 * Usher had the megahit OMG that topped the pop charts and didn't really make a dent in the urban market.
 * And, in 2010, Kelly Rowland released three singles, each for different market - Commander for international (i.e. non-US) audiences, Rose Colored Glasses for American pop radio, and Grown Woman for the urban market.
 * Ce Ce Peniston might have been the prototype, with one foot in house music, and the other in R&B/New Jack Swing.
 * For not only a whole generation but perhaps a largely white audience who grew up with Phil Collins as the drummer (and later, also lead singer) of Genesis, his transformation from white British art-rocker with hair down to his belly and a long white robe singing about squonks and eleventh Earls of Mar to 1980's, commercial, electronic blue-eyed soul/funk/soft rock singer in a suit and tie singing "Su-Su-Sudio" can be controversial. For a generation (and skin color) who know Phil's pop hits through black radio playing his MTV-era hits and who wouldn't necessarily pick up a copy of A Trick Of The Tail, you would have the likes of Ice T put in his place a white, smarmy, hipster rock journalist picking on the Phil Collins CD's in Ice's collection during an interview with Ice by responding, "Don't you mess with my Phil!".
 * Similar to the Dionne Farris example above, this trope can apply to Signature Songs as well. If a artist is popular in more than one demographic it's HIGHLY likely that each group has their own opinion of what that artist's signature song is.
 * The death of R&B singer Aaliyah completely gutted the Hip Hop and R&B community with huge outpourings of mourning and tributes. When it came around to the mainstream media to react, most of the entertainment news outlets (that primarily cover white celebs) didn't even have her death as the top story, and they had to use Gladys Knight (Aaliyah's former aunt and close family friend) in order to make her more relevant to that audience.
 * Same could be said for the aforementioned Selena.
 * Ellen DeGeneres touched upon this when Tupac Shakur died. Noting that the mainstream media were more interested in her coming out of the closet.
 * This is fairly common with black celebrities
 * Like the Whitney Houston example above, the same could be said for N'Sync. This trope combined with the But Not Too Black trope was how they were marketed by their handlers. They didn't start courting urban audiences till the Celebrity album.
 * It is fiendishly difficult for J Pop and K Pop artists to cross over to American shores. Even Utada Hikaru (who is American) has had a difficult time despite switching up the production of her second U.S. album. And she's one of the most popular music artists in Japan and still has the worldwide record for most albums sold in a week. Both she and Boa tried for U.S. success, but couldn't expand beyond the people who already were fans.
 * Between both of the genres however, K Pop has a slight edge over them as the genre is very popular among Asians while J Pop at the moment is stuck in it's own nation.
 * Instead of making a straight dance song, a lot of singles from the early-90s on come with dance mixes to get play in clubs and on dance radio shows, adding in bigger beats and a beginning drum track for transitions. Depending on the release, these tracks might be included as a bonus track on an album, on the single, or only on a special "DJ Mix" single. This means if you don't hear it in a club, you probably won't hear this version at all.
 * A main cause of Covered Up, where an artist in one genre covers a song from another.
 * Country Music. According to one recent survey, 38% of American adults are country music fans... but 25.4% of that group only listens to country music. While the stereotype of country music listeners being exclusively down-market blue collar types is no longer true, regional and demographic appeal does vary. Some urban markets, including America's #1 media market, New York City, have few to no country stations. And with that, little to no knowledge of any country act who hasn't crossed over into pop (e.g. Taylor Swift and Lady Antebellum). Country is also one of the whitest genres in music.
 * As far the United Kingdom is concerned, pop music in languages other than English does not exist.
 * Very, very occasionally a song in French (Dominique, Je t'aime) or German (Kraftwerk Autobahn) or Italian (Vado Via) will hit the British charts. These average about one a decade, discounting things like the Beatles' Michelle (the French bits are a bit pidgin). The last foreign-language hit was probably Enigma's Sadeness. In 1994.

New Media

 * A lot of Internet culture and memes cause this.

Newspaper Comics

 * The Boondocks managed to overcome this.
 * Indeed, most comic strips start out in only one newspaper (usually a paper in a region of a country where the cartoonist works) and then are nationally syndicated, sometimes not until years later. More than a few strips have ended up dying on the vine - at least in some parts of the country - due to censorship.

Radio

 * Radio is usually blamed for this phenomenon when it comes to music isolation.

Sports

 * The Ultimate Fighting Championship, AKA The UFC has dealt with this for problem for awhile, mainly due to the sports previous violence image and detractors being unable (or unwilling) to get past it. Around the late 90's the UFC repackaged the sport as "Mixed Martial Arts" in an attempt to be taken seriously. It took a reality television show to gain wide acceptance. UFC has outsold boxing quite handily ever since '06, with '07 being the exception. Most of the sports broad casting community to this day refuses to except it as a legit sport. Some even went as far as to accuse it of being a poor (white) person's version of boxing, due to the UFC's heavy young white male demographics compared to boxing. Today, while most people couldn't them you the names of the champions in each weight class, could at least tell you what the sport is. And with the UFC's broadcasting deal with FOX, the days of the UFC being considered a niche sport are most likely over.
 * X-treme Sports
 * College Basketball/Football's SWAC division.
 * The MEAC too. Many of the schools in both divisions have traditions that are every bit as entrenched as the more well-known Southeastern Conference (SEC) schools. For example, each year a football team from a SWAC school meets a team from the MEAC in Indianapolis for the Circle City Classic. The festivities that lead up to the game draw more people to Central Indiana than any annual event besides the Indy 500, yet it's almost completely unknown to non African-Americans outside of the area.
 * Soccer, of course. (at least in North America)
 * That's a Cyclic Trope. I think every generation we'll have a Pele or a David Beckham, but they'll be few and far between.
 * But there are millions of soccer fans in America—enough to post decent numbers for European soccer broadcasts on ESPN/FSC and keep Major League Soccer's numbers growing. However, unless it's World Cup time, non-fans are unlikely to hear anything about soccer in America unless they very closely follow sports journalism.
 * The same is also true for Grid Iron/American Football. While there are teams and leagues across Europe (Britain hosts more than a few) the sport is largely ignored by the mainstream press except around the Super Bowl.
 * Until the late nineteenth century, sports were generally for the wealthy. Once athletic contests began to appeal to middle-class and working-class people, many of the more elitist sports (polo, regattas, fencing, etc.) fell into obscurity or semi-obscurity.
 * This leads to the fact the IOC has to help the sports that aren't lucrative outside the Olympic Games, particularly during the recent recession.

Theater

 * Tyler Perry, until recently.

Video Games

 * Games in general, with rare exceptions such as Pac-Man and Mario.
 * GTA's radio stations are a great example of this. Some of the dj's even take shots at the other stations.
 * PC exclusive games might count as well.

Other

 * Most major sci-fi/anime/comics conventions (except for San Diego ComicCon, which has become very mainstream and a crucial stop on many promotional tours) are not nearly as well known outside of various geek communities (and the locals of the particular city where the con is usually held). For instance, Dragon*Con is well known to geeks and Atlantans, but not very many else.
 * Judging from the sheer amounts of game-related announcements, one would think the event is now E 3 2.0.
 * Quite a few white people appear to be unaware of the But Not Too Black controversy. Ironic since every daytime talk show known to man from Ricki Lake to Jenny Jones to Tyra Banks has covered this issue.
 * Inversely a lot of black people think this issue is only seen within their community, but it's very prominent in Asian and Hispanic communities as well.
 * Back in the times of the Cold War, it was possible to receive West German TV-programs in most places of East Germany - except in the area of the Dresden Basin. Because of this lack of information regarding Western news coverage and of course also Western pop culture, it was accordingly called the "Valley of the Clueless".
 * In turn, few West Germans bothered to consume East German pop culture, which now can cause Pop Culture Isolation in re-unified Germany.
 * TONS of internet models and celebrities that are made famous through the net are more or less obscure in pure mainstream media. Basically any model or obscure female actress that's ever appeared on or in Stuff magazine, Maxim, or FHM. Sure people on the net are familiar. But to the general public they might as well be nobodies
 * Their attractiveness is what help them get noticed in the first place despite being D-Listers. Case in point Jaime King pre-Sin City. You'd be hard pressed to find someone in the mainstream who knew who she was. But Maxim magazine and people on the internet did. Interestingly enough she hasn't done anything mainstream since. Likewise with Emmanuelle Vaugier prior to CSI: NY.
 * Some of these actors/models/actresses careers can be chalked up to a combination of this trope, Hey, It's That Guy!, Critical Dissonance, Hype Backlash, and I Coulda Been a Contender all rolled up into one. Usually in that order too. (see also Hollywood Hype Machine)
 * Cindy Margolis probably being the Ur Example. From the way the internet treated her you'd thought she was a break out star or something.
 * Then there's Tila "Tequila" Nguyen.
 * Amber Rose as well is gradually heading down this road thanks to photoblogs. Dating Kanye West probably helped.
 * Music video models are the same way obviously. Lots of rock fans know who Bobbie Brown, and Tawny Kitaen are. While urban music video watchers are probably only vaguely familiar if that. Same goes for models that appear in urban music video like Esther Baxter, Melyssa Ford, and Summer Walker etc...Even in that context there's not a lot of people who know them outside certain internet circles (I.E. Hip Hop Image Boards, where they're well known and popular). But bring their names up in certain mainstream social circles and you would get blank stares.
 * Unfortunately Black History Month has become this instead of being seen as part of American history too. Especially Native American History Month which is November.
 * Most popular porn stars who aren't Jenna Jameson or Ron Jeremy... although some might get some mainstream attention primarily from news outlets because of some type of controversy surrounding said performers or the industry itself, like the Belladonna and Sasha Grey Primetime Live/The Insider news interviews (respectively) for example.
 * Interestingly enough even the most obscure porn star can have tens of thousands of twitter followers.
 * This trope with a little dusting of racism might be the cause of all of the numerous segregated proms in the south, which have offended black teens and other minority teenagers.
 * A lot of cynics think this is why interracial relationships/marriages can't work unless they're from the same socio-economic background and are fully assimilated into mainstream American culture (or whatever culture their significant other is from).
 * E! network host Sal Masekela noted in an interview with Jay-Z that entertainment news media and tabloids generally don't cover black celebrities. Quite frankly, black celebs should probably see that as a blessing in disguise.
 * Unfortunately, on the flip side there's urban gossip mags and blogs to compensate for this, especially during the past ten years.
 * The aforementioned magazines like FHM, Maxim, Stuff, and so on run on this trope. It's a pretty safe bet that most people outside the internet have never heard of half of the listed people in Maxim's Hot 100. Just mention the name Gemma Atkinson to some random American and they wouldn't know who the hell you're talking about.
 * These mags have black counterparts as well like King, SMOOTH, and Black Men Magazine. And most of the models within are hardly known outside of Hip Hop message boards.
 * If a country has regions that speak different languages they tend to develop their own cultures based on these languages.
 * In Canada, Quebec has many musicians, actors, and comedians that are unknown in the rest of Canada unless they also do English-language work.
 * Linux powers sites like Google (as well as Android) and hardcore geeks run it on their desktops, but among people who even know what an operating system is in the first place, they're more likely to be familiar with Windows or Mac OS X.