The Warsaw Pact or Warsaw Treaty, officially named the Treaty of Friendship, Co-operation and Mutual Assistance, was a military organization of Central and Eastern European Communist states. It was established in 1955 to counter the perceived threat from the NATO alliance (which had been established in 1949). The creation of the Warsaw Pact was prompted by the integration of a "re-militarized" West Germany into NATO via ratification of the Paris Agreements. The Pact lasted throughout the Cold War until, following the collapse of Communist states in Europe and political changes in the Soviet Union, countries began withdrawing in 1991. The Warsaw Pact was officially dissolved in July 1991.
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