Exactly What It Says on the Tin: When a character is referred to pretty much exclusively by where he comes from. Or at least, where everyone assumes he's from.
This is Truth in Television, if you look in historical documents, you will find that many people were distinguished by where they came from (other common identifiers included trade or profession and distinguishing features). When surnames became common, towns of origin were often assigned as family names. If the person isn't actually from the place he is named for, it can become an Ironic Nickname. This is also one popular means for pen names.
- Kasuga Ayumu in Azumanga Daioh is only known as Osaka.
- Trope was enforced in-universe by one of her new friends, whose idea the nickname originally was. Also lampshaded/discussed as said friend declared on the spot that shows have characters from Osaka only known as Osaka (and that such is funny). Never mind that Ayumu points out she spent only a year or so of her life in Osaka; the friend is a Giver of Lame Names.
- Elie in Rave Master, who asumes the tattoo on her arm is her name after getting Laser-Guided Amnesia. It's actually both her home town and the coordinates of said town.
- In Bleach there's Kenpachi Zaraki and Yachiru Kusajishi, both of whom didn't have last names, and so they took the districts they originated from (Zaraki and Kusajishi, respectively). In Kenpachi's case, its even more so, since Kenpachi is a title given to the strongest Shinigami. So he's really 'The Kenpachi from Zaraki'.
- Some writers of Superman comics have picked up Lois calling Clark "Smallville" from Superman: The Animated Series and Smallville.
- Dennis Finnegan, a gangster who was framed for murder by corrupt cops in the Robin Series, is called Dublin because he's from Dublin Ireland.
- Blazing Saddles features Gene Wilder playing Jim, AKA The Waco Kid.
- In The Adventures of Buckaroo Banzai Across the 8th Dimension, Jeff Goldblum's character is known only as "New Jersey".
- Coyote Ugly - When Violet first takes a job at the bar, she's known as Jersey, her home state.
- El Dorado: Mississippi, born on the river, and mostly called that because of his Overly Long Name.
- Subverted in Forrest Gump.
"There was Dallas, from Phoenix; Cleveland - he was from Detroit; and Tex... well, I don't remember where Tex come from." (Played straight there, Tex was from Texas.)
- Played with in Gunhed with the character "Brooklyn" who's Japanese...and wears a Dodgers baseball shirt. He doesn't get it because by that time the team was in L.A.
- Hudson Hawk. The title character's real first name is Eddie, he grew up in a town called Hoboken on the Hudson River in New Jersey.
- Indiana Jones is at first assumed to be this, until Indiana Jones and the Last Crusade, where we learn he took his name from his dog.
- Medicine Man, Dr. Rae Crane is known as Bronx.
- Poolhall Junkies - The Greek.
- Almost every character in Zombieland. At first it's just something that Tallahassee insists on to avoid emotional ties with other survivors, but through the course of the movie, almost every character ends up only being identified by where they are from (or, in the Flash Back, by their apartment numbers), with the only exceptions being The Cameo and, at the end of the movie, Wichita.
- Alabam, Grady Sutton's character from Hal Roach's "Boy Friends" short subject series from the 1930's.
- Inverted in Doc Hollywood, in that that's where Ben Stone was going, not where he was from.
- A fairly well-known example from The Bible is Jesus of Nazareth, sometimes also known as The Nazarene.
- A few other names in the New Testament and early saints fit this pattern, which is not all that surprising due to some given names being extremely popular, e. g. Joseph of Arimathea and Mary of Egypt. In the case of Mary of Magdala, the Hometown Nickname became a name in its own right (Magdalena, Maddalena, Madeleine etc.). Averted by Saul of Tarsus, who changed his name to Paul - just Paul.
- Doc Pseudopolis is a high ranking member of Ankh-Morkpork's guild of gamblers on Terry Pratchett Discworld. He makes a living off of people whose fathers never warned them not to gamble with a man named Doc or anyone named after a city.
- The Discworld Companion lists the guild leader as Scrote Jones.
- Santiago of Twilight is from Santiago. Given her age, not only does no one call her by her given name, almost no one knows it.
- Max, best friend to Codex Alera hero Tavi, frequently refers to Tavi as "Calderon." In a similar vein, Kitai refers to him as "Aleran" even when she refers to other Alerans by name.
- Happens in the Warrior Cats novel Night Whispers. The ThunderClan warrior Ivypool is kidnapped by a ShadowClan patrol and held prisoner in their camp. There, a group of ShadowClan kits give her the nickname "Thundercat".
- The Adventures of Brisco County, Jr.: Brisco goes undercover using the name "Kansas Wily Stafford" ("Kansas" for short). Then the real Kansas Wily Stafford shows up...
- Brisco, however, is an inversion. People keep assuming Brisco County is where he's from, a point which he has to clarify not to be the case.
- CSI: NY: Danny calls Lindsay "Montana". It's only a partial example, as he seems to be the only one on the show to call her that.
- Lois calls Clark this in Smallville
- Survivor has an example in three different seasons with "Boston" Rob. Justified due to his first season running into the One Steve Limit.
- The old TV show, The Virginian.
- There was a travelogue show on UK Channel 4 in the mid 90s in which the presenter's sidekick was known as Luton, because she was from... that's right.
- Heroes has the Haitian and the German.
- Star Trek: Voyager:
- Neelix calls Tuvok "Mr. Vulcan" while referring to everyone else by rank & name.
- In one episode Chakotay is captured by a group of Kazon, who use "Starfleet" as his name.
- In the pilot, B'Elanna calls Kim "Starfleet".
- One sketch on The Kids in the Hall deals with the "Cincinnati Kid" (not that one), whose father was the Cincinnati Kid until he was born, and who will remain the Cincinnati Kid until he produces offspring of his own. He shows up at a bar in Toronto looking for the "Toronto Kid", and the two square off in a Zero Chops brawl until the Toronto Kid gets a phone call saying his wife has given birth to the new Toronto Kid... and the Cincinnati Kid goes off in search of him.
- In Kamen Rider Ghost, Those Two Guys who study under Onari go by Shibuya and Narita.
- In Red vs. Blue, the initial explanation for Tex's name is "because she's from Texas." Later it's retconned into being a shortening of her codename "Texas".
- In The Nails classic 88 lines about 44 women this is stated about Seattle.
- In Gypsy the boys Rose picks up to serve as a chorus for June's act are known only by the names of the cities where she "acquired" them.
- Nevada Smith, an Indy parody, in Apogee Software's Pharaoh's Tomb.
- Grand Theft Auto: San Andreas has Kent Paul (Paul from Kent).
- Subverted in the Tex Murphy series, where the titular character's nickname comes from leaving a Texas-shaped hole in the ceiling after a childhood accident.
- Arizona Rose, heroine of two Big Fish games.
- Dragon Age has a few.
- Anders, from Dragon Age: Origins Awakening and Dragon Age II, is called Anders because he comes from the kingdom of the Anderfels. Nobody knows what his real name actually is; it's possible that he himself no longer remembers.
- In Dragon Age: Inquisition, minor side character Fairbanks goes by that name because he was born in a location called the Fair Banks Cottage. His real name can be revealed through a side quest.
- A number of other minor characters throughout the series have names based on their place of origin, such as Michel de Chevin and Frederic of Serault.
- Yosemite Sam, possibly.
- Lois calls Clark "Smallville" in Superman: The Animated Series. This was later picked up in Smallville (see Live-Action Television, above).
- Superted has the Big Bad, Texas Pete.
- On King of the Hill, Cotton Hill has war buddies named Brooklyn and Fat Brooklyn.
- The second generation swordsmith of the Kanesada family known as Izuminokami Kanesada ("the kami of Izumi province"), otherwise called Nosada, real given name unknown.
- The sixth generation Hinin Kiyomitsu ("Slumdog Resident" Kiyomitsu), otherwise known as Kashū Kiyomitsu (Kashū being another name for Kaga province), whose sword was purportedly used by Okita Sōji of The Shinsengumi.
- Munechika, otherwise known as Sanjō Kokaji Munechika (Sanjō being the name of a street in Kyoto), smith of the national treasure Mikazuki Munechika, one of the tenka goken.
- Let's just say this is incredibly common among historical Japanese swordsmiths.
- An example Older Than Print: the medieval German poet known only as der Tannhäuser (the one from Tannhausen). Even his given name is not known.
- Tex Avery, born Frederick Bean Avery in Taylor, TX.
- Tex Ritter, country music singer and Western actor, best known today as the father of John Ritter.
- Tennessee Williams, sort of. He wasn't from Tennessee, but his father was.
- Giovanni Battista Bernardone was nicknamed Francesco (little Frenchman) by his merchant father, who had not been present at his birth as he was on a business trip to France. Francesco later became known as St. Francis of Assisi and his geographical nickname was adopted by lots of people as a Christian name.
- Leonardo da Vinci.
- Prince Leopold of Anhalt-Dessau, one of the leading generals of the first three kings of Prussia, was commonly referred to as der alte Dessauer (the old man from Dessau).
- El Greco, a Greek artist living in Spain.
- General François Fournier is usually referred to as Fournier-Sarlovèze, being from the town of Sarlat.
- The phenomenon occurs not just with people, but also with items of food (e. g. Hamburger, Frankfurter), drinks (Manhattan, Champagne, Port), dances (Charleston), coaches and cars (Landau, Limousine), cricket deliveries (Yorker), etc. In these cases, the operative nouns ("sausage," "wine," "coach," etc.) have become redundant and are pretty much always left out.