The Warsaw Pact

The Warsaw pact, or the Treaty of Friendship, Co-operation and Mutual Assistance, was established on May 1st 1955, supposedly to counter the allowing of West Germany into NATO.  It linked all of the communist countries in Europe except Yugoslavia, although over time revolutions forced more and more nations to leave the alliance.  The pact was officially denounced in 1991, but details regarding the Warsaw Pact were not available for the public until 2005.  Now, most of the countries in the Pact are members of the European Union.