Humanities › Geography The Warsaw Pact History and Members Member Countries of the Eastern Bloc Group Share Flipboard Email Print Alphathon/Wikimedia Commons/CC ASA 3.0U Geography Political Geography Basics Physical Geography Population Country Information Key Figures & Milestones Maps Urban Geography By Matt Rosenberg Geography Expert M.A., Geography, California State University - Northridge B.A., Geography, University of California - Davis Matt Rosenberg is an award-winning geographer and the author of "The Handy Geography Answer Book" and "The Geography Bee Complete Preparation Handbook." our editorial process Matt Rosenberg Updated September 30, 2018 The Warsaw Pact was established in 1955 after West Germany became a part of NATO. It was formally known as the Treaty of Friendship, Cooperation, and Mutual Assistance. The Warsaw Pact, made up of Central and Eastern European countries, was meant to counter the threat from the NATO countries. Each country in the Warsaw Pact pledged to defend the others against any outside military threat. While the organization stated that each nation would respect the sovereignty and political independence of the others, each country was in some way controlled by the Soviet Union. The pact dissolved at the end of the Cold War in 1991. History of the Pact After World War II, the Soviet Union sought to control as much of Central and Eastern Europe as it could. In the 1950s, West Germany was rearmed and allowed to join NATO. The countries that bordered West Germany were fearful that it would again become a military power, as it had been just a few years earlier. This fear caused Czechoslovakia to attempt to create a security pact with Poland and East Germany. Eventually, seven countries came together to form the Warsaw Pact: Albania (until 1968)BulgariaCzechoslovakiaEast Germany (until 1990)HungaryPolandRomaniaThe Soviet Union The Warsaw Pact lasted for 36 years. In all of that time, there was never a direct conflict between the organization and NATO. However, there were many proxy wars, especially between the Soviet Union and the United States in places such as Korea and Vietnam. Invasion Of Czechoslovakia On Aug. 20, 1968, 250,000 Warsaw Pact troops invaded Czechoslovakia in what was known as Operation Danube. During the operation, 108 civilians were killed and another 500 were wounded by the invading troops. Only Albania and Romania refused to participate in the invasion. East Germany did not send troops to Czechoslovakia but only because Moscow ordered its troops to stay away. Albania eventually left the Warsaw Pact because of the invasion. The military action was an attempt by the Soviet Union to oust Czechoslovakia's Communist Party leader Alexander Dubcek whose plans to reform his country did not align with the Soviet Union's wishes. Dubcek wanted to liberalize his nation and had many plans for reforms, most of which he was unable to initiate. Before Dubcek was arrested during the invasion, he urged citizens not to resist militarily because he felt that presenting a military defense would have meant exposing the Czech and Slovak peoples to a senseless bloodbath. This sparked many nonviolent protests throughout the country. End of the Pact Between 1989 and 1991, the Communist parties in most of the countries in the Warsaw Pact were ousted. Many of the Warsaw Pact's member nations considered the organization to be essentially defunct in 1989 when none assisted Romania militarily during its violent revolution. The Warsaw Pact formally existed for another couple of years until 1991—just months before the USSR disbanded—when the organization was officially dissolved in Prague.