A military alliance of communist nations in eastern Europe. Organized in 1955 in answer to NATO, the Warsaw Pact included Albania, Bulgaria, Czechoslovakia, East Germany, Hung … ary, Poland, Romania, and the Soviet Union.It disintegrated in 1991, in the wake of the collapse of communism in eastern Europe and the Soviet Union.he treaty was signed in Warsaw on 14 May 1955, and the pact was dissolved in Prague on 1 July 1991. The Warsaw Pact no longer exists. It was an alliance of the Eastern Bloc countries, established in 1955 by the Soviet Union as a counterpart to NATO.