Soviet Union: A communist state that existed from 1922 to 1991 in Eurasia. It comprised multiple republics including Russia and was led by the Communist Party.
Iron Curtain: A metaphorical term coined by Winston Churchill during the Cold War representing the divide between Western Europe (capitalist) and Eastern Europe (communist), which was heavily influenced by Soviet control.
Eastern Bloc: The group of nations in Eastern Europe that were under Soviet influence during the Cold War period, including countries like Poland, East Germany, Hungary, Czechoslovakia, etc.