Soviet Union was a federal socialist state in Eurasia that existed from 1922 to 1991. Its official name was the Union of Soviet Socialist Republics (USSR). The Soviet Union was established following the Russian Revolution and the Russian Civil War, and it was governed by the Communist Party of the Soviet Union.
The Soviet Union consisted of multiple Soviet republics and was one of the world's two principal superpowers during much of the Cold War, alongside the United States. Its capital was Moscow. The Soviet Union was dissolved in 1991, and its constituent republics became independent states.