* The German Democratic Republic (GDR): The GDR was a communist state that existed in East Germany from 1949 to 1990. It was closely allied with the USSR and was a member of the Warsaw Pact, a military alliance of communist countries.
* The People's Republic of Poland (PRL): The PRL was a communist state that existed in Poland from 1947 to 1989. It was closely allied with the USSR and was a member of the Warsaw Pact.
* The Czechoslovak Socialist Republic (CSSR): The CSSR was a communist state that existed in Czechoslovakia from 1948 to 1992. It was closely allied with the USSR and was a member of the Warsaw Pact.
* The People's Republic of Hungary (PRH): The PRH was a communist state that existed in Hungary from 1949 to 1989. It was closely allied with the USSR and was a member of the Warsaw Pact.
* The Socialist Republic of Romania (SRR): The SRR was a communist state that existed in Romania from 1947 to 1989. It was closely allied with the USSR and was a member of the Warsaw Pact.
* The People's Republic of Bulgaria (PRB): The PRB was a communist state that existed in Bulgaria from 1946 to 1990. It was closely allied with the USSR and was a member of the Warsaw Pact.
* The Socialist Federal Republic of Yugoslavia (SFRY): The SFRY was a communist state that existed in Yugoslavia from 1945 to 1992. It was closely allied with the USSR, but was not a member of the Warsaw Pact.
In addition to these countries, the USSR was also allied with a number of other communist movements and organizations around the world.