USSR
The USSR was a federal state of 15 republics headed by a single communist party. This federation existed from its proclamation on December 30, 1922, to its dissolution on December 26, 1991.
The 15 republics were:
- Russian Soviet Federative Socialist Republic
- Estonian SSR
- Latvian SSR
- Lithuanian SSR
- Byelorussian SSR
- Ukrainian SSR
- Moldavian SSR
- Georgian SSR
- Armenian SSR
- Azerbaijan SSR
- Kazakh SSR
- Uzbek SSR
- Turkmen SSR
- Tajik SSR
- Kirghiz SSR