Howdy, Comrades!
So, yeah, this is my first post. I'm working on a Fallout fan project - "Fallout: Metropolis". No, it's not a mod like Project Brazil or anything like that. Just a little thing some friends and I are working on. ANYWAY, Fallout: Metropolis takes place in the ruins of New York City - which is surrounded by a year-long nuclear winter, and is divided into two different worldspaces: the Underground, and the New York Wasteland.
After the atomic destruction of the Middle East by the European Commonwealth, in the decades leading up to the Sino-American War, the Mayor of New York initiated a massive expansion and renovation of the New York subway system. The reasons for this expansion were three-fold. One, the skyrocketing cost of oil meant that more people were taking the subway than ever before, and the old system wasn't capable of meeting the increased demand. Two, it was seen as a way to keep all the unemployed busy and not listening to the communist sympathizers that were being suppressed in the city. Three, the writing was on the wall. War was coming. A war to end all wars. And if New York was to survive, it's salvation lay underground.
New lines were built, stations were expanded, and Vault-Tec was brought in to reinforce the walls and ceilings, and install emergency airlocks and radiation scrubbers (though a group of Vaults - connected by a separate rail line - was also built, accessible only through a labyrinthine network of utility tunnels). And thus, the New York Underground became America's largest fallout shelter.
It was finished just as the bombs dropped, in October of 2077. New York's air defense system managed to shoot down most of the bombs, but enough made it through to kill the city. Several thousand people made it underground, but most of the city's population died clawing at the closing airlock doors - screaming for God to open them, as the flashes of fire and ionizing radiation burned the flesh off their bodies. And the really unlucky ones became New York's massive Ghoul population.
The "Provisional Government of New York City" - a regime that administered almost all of the Underground - collapsed after about 30 years. This ushered in a 64-year period of constant bloodshed in the Underground known as "the Great Chaos". The Great Chaos ended with the Treaty of Vault 44, and a new political/territorial order was formalized.
Which includes the subject of this post (FINALLY! He gets to the flag!): the People's Republic of Chinatown (Oh no! More exposition! GYAAHH!).
Prior to the Great War, New York's Chinatown was a hotbed of Chinese spies and operatives, as well as native-born American communist sympathizer cells. In fact, things got so bad, that the New York National Guard was brought in to keep Chinatown under martial law.
But when the world ended, these communists ended up being the best-organized and best-armed group among the survivors that fled to Chinatown's underground to escape the fires of the apocalypse.
Some politics happened, the Great Chaos happened, and the Vault 44 Treaty happened, and the People's Republic of Chinatown was born.
Today, only half of the PRC's population is actually of Chinese descent, though almost every Chinatown citizen can speak Chinese at least as a second language. The PRC controls 13 stations, and has another five "independent" stations under its sphere of influence. In addition, they also control the vast network of tunnels and secret rooms built by the Triads and Tongs in the early 20th century. Many of Chinatown's stations are lit with paper lanterns, with walls of socialist-realist murals celebrating the values of cooperation and common struggle in the post-apocalyptic world.
Chinatown is a single-party market socialist state, run by a Ghoul named Chairman Hong. Hong was originally the leader of a Crimson Dragoon stealth unit tasked with staging assassination and sabotage operations against targets on US soil. But after the war, all Hong cared about was the safety of his newfound people. He has been in power for the last 183 years, and remains a popular leader.
So anyway, the flag of Chinatown is basically the flag of the People's Republic of China, only with the Chinese characters for "Chinatown" replacing the big star. Though Chinatown isn't Maoist anymore, they still like Maoist symbolism, and at this point, it's really more of a cultural thing, than a political thing.