Warsaw Pact, the common name for the Warsaw Treaty of Friendship, Cooperation, and Mutual Assistance. This treaty was signed at Warsaw, Poland, on May 14, 1955, by the Soviet Union and its seven East European satellites—Poland, Czechoslovakia, Hungary, Albania, Romania, Bulgaria, and East Germany. The pact established a mutual-defense organization, a military alliance intended as a counterweight to the North Atlantic Treaty Organization. A unified command under Soviet direction was created, with headquarters at Moscow.

Albania, which broke relations with the Soviet Union in 1961, formally withdrew in 1968. In 1969 the Soviet Union permitted Warsaw Pact forces to be placed under joint command with a multinational staff. During 1989–91 Communists fell from power in most of the nations of Eastern Europe. Also during this period Germany was reunited. These events marked the end of the Cold War and in 1991 the Warsaw Pact alliance was disbanded.