The Warsaw Pact (WP) or Treaty of Warsaw, formally the Treaty of Friendship, Cooperation and Mutual Assistance, was a collective defense treaty signed in Warsaw, Poland, between the Soviet Union and seven other Eastern Bloc socialist republics of Central and Eastern Europe in May 1955, during the Cold War.The term "Warsaw Pact" commonly refers to both the treaty itself and its …

On 20–21 August 1968, Czechoslovakia was jointly invaded by four Warsaw Pact countries: the Soviet Union, Poland, Bulgaria and Hungary. About 250,000 Warsaw Pact troops (afterwards rising to about 500,000), supported by thousands of tanks and hundreds of aircraft, participated in the overnight operation, which was code-named Operation Danube. Romania and Albania refused …

The Warsaw Pact was created in reaction to the integration of West Germany into NATO in 1955 per the Paris Pacts of 1954, but it is also considered to have been motivated by Soviet desires to maintain control over military forces in Central and Eastern Europe.