District 13 used to produce graphite for the Capitol before the Dark Days. Afterwards, District 13 was said to be completely oliberated but they secretly lived underground for years while the Hunger Games ran on...

District 13 was never and will never be part of the Hunger Games. They live almost as a seperate nation from Panem and their districts.

District 13 is very organized and orderly. They follow the communist order: everyone is equal and everyone is treated as equals.

District 13 is very strict and produces weaponary such as nuclear bombs. This can refer to the Cold War between USA (the Capitol) and Soviet Union/Russia (District 13). District 13 is very similiar to the Soviet Union before it turned back to socialism again.