1950s: The Warsaw Pact is signed binding the Soviet Union and its Eastern European satellites, including Poland, together in a military alliance. The member countries include Albania, Bulgaria, Czechoslovakia, German Democratic Republic (East Germany), Hungary, Poland, Romania, and the Soviet Union. This alliance allows the Russian Red Army to maintain a presence in each country and is meant to parallel the NATO alliances formed at the conclusion of World War II.

Today: Although the Warsaw Pact is officially renewed in 1985, it has begun to dissolve. In 1968, Albania is the first country to leave. Over the next twenty-five years, several other countries also choose to leave the alliance, and, in July 1991, the Warsaw Pact is officially dissolved. In 1999, the Czech Republic, Hungary, and Poland join NATO. In 2004, Bulgaria, Romania, and several separate member states of the former Soviet Union also join NATO.

1950s: Nikita Khrushchev...