The Warsaw Pact was the Eastern bloc countries’ answer to the North Atlantic Treaty Organization (NATO). Seeing the Western nations form a strong alliance, in May 1955 the Soviet Union and its allies met in Warsaw, Poland, where they signed a treaty agreeing that they, too, would mutually defend one another. The eight member nations were Albania (which withdrew in 1968), Bulgaria, Czechoslovakia, East Germany, Hungary, Poland, Romania, and the Soviet Union. The Warsaw Pact was headquartered in Moscow and, in addition to discouraging attacks from Western bloc/NATO countries, the organization also sought to quell any democratic uprisings in Warsaw Pact nations.

But in 1990 the pact and the Soviet Union’s control of it weakened as democracy movements in member nations could not be put down. As the former Eastern bloc countries underwent relatively peaceful revolutions, Warsaw Pact members began announcing their intentions to withdraw from the organization. East Germany withdrew when it was reunified with West Germany, and the restored Germany joined NATO (in 1990). The Warsaw Pact was dissolved by the remaining member nations in 1991.