The USSR and seven European countries signed the Warsaw Pact on May 14, 1955 as a response to NATO, to have a similar alliance on the opposition side. Members included Albania, Czechoslovakia, East Germany, Bulgaria, Poland, Romania and the Soviet Union. Through the treaty, member states promised to defend any member that may be attacked by an outside force, with the unified command under a leader of the Soviet Union. The Warsaw Pact ensured that most European nations were aligned in one of two opposing camps and formalized the political divide in Europe that became prevalent World War II.

Main Reason for  the Warsaw Pact

The Warsaw pact was only signed 6 years after the NATO alliance was made. The reason for this is because NATO allowed West Germany to join the alliance and start a small army again. The Soviet leaders were very apprehensive about this, especially with WWI and WWII still fresh in mind and decided to get security measures in place in the shape of a political and military alliance. The pact however only lasted until 1991, when the Soviet Union came to an end