Over a span of about four decades, countries within the Eastern Bloc would try to break free, and the Soviet Union would bring them back under control either through internal pressure, martial law or, as a last resort, military invasion.
During World War II (1939–45), the United States and the Soviet Union worked together as allies, as both were threatened by Hitler's increasing aggressiveness and desire for dominance. After the war, however, when both countries emerged as world powers, the alliance quickly dissolved. Stark differences between two political ideologies -- democracy and communism -- as well as desire for power preservation, made both countries more concerned with self-protection and promotion, than with mutual cooperation.
The United States used its power to try to protect existing democratic governments around the world. The Soviet Union, using the influence it had gained through the war, established and enforced communist rule and created an alliance of countries on its eastern borders that stood as a buffer between the Western world and itself -- a formation that became known as the "Eastern Bloc."
From Allies to Satellites
In the years following the war, countries were understandably nervous about potential future military conflicts, particularly with Germany. The Soviet Union had already established alliances with countries on its western border such as Poland, Czechoslovakia, Romania, and Bulgaria -- having used its military armies to help liberate these countries from German occupation.
By the end of WWII, the Soviet Army under the leadership of Joseph Stalin (1878–1953) occupied Bulgaria, Romania, Hungary, Poland, portions of Czechoslovakia and Eastern Germany. These countries, which all came under Communist control largely due to the influence of the Soviet Union, were referred to as the Eastern Bloc. China, Yugoslavia, and Albania also adopted Communist governments in the 1940s. Although China was initially considered to be part of the Eastern bloc, it later broke with the Soviet Union.
After the war, the Soviet Union had no desire to withdraw from these occupied countries. It wanted to maintain the buffer zone as insurance against any future aggression from Germany and to uphold its military and political power in the region. It established treaties that allowed it to continue its military presence, and essentially, guaranteed its Communist political control.
NATO and the Warsaw Pact
The Soviet Union's confidence in its control over its allies was shaken in the late 1940s when Yugoslavia, under the leadership of Josip Broz Tito (1892–1980), gradually turned away from Stalin and began to look elsewhere for trade and economic assistance. Friction increased when Tito liquidated a faction of the Yugoslav Communist Party loyal to Moscow. In 1948, the Soviet-controlled Communist Information Bureau (Cominform), expelled Yugoslavia from its ranks and publicly denounced the country. No military action was taken, however; most believe the inaction was due to the fact that Yugoslavia did not share a border with the Soviet Union.
Meanwhile, countries like Belgium, France, the Netherlands, and the United Kingdom grew nervous about Communist expansion, and saw a need for mutual defense. They drafted the North Atlantic Treaty on April 4, 1949. The new treaty formed the North Atlantic Treaty Organization (NATO), with members including the U.S., Canada, Belgium, France, Luxembourg, the Netherlands, the United Kingdom, Denmark, Iceland, Italy, Norway and Portugal. The Soviet Union saw the formation of NATO as a direct threat, particularly when West Germany joined the group on May 9, 1955. To give structure to their alliance with the Eastern Bloc countries, and to provide an official counterweight to NATO's presence in East/West diplomacy, the Soviet Union and its Communist allies also signed a treaty on May 14, 1955, known as the Warsaw Pact. The alliance included the Soviet Union, Albania, Bulgaria, Czechoslovakia, East Germany, Hungary, Poland and Romania -- all the Communist countries of Eastern Europe except for Yugoslavia.
The Eastern Bloc Eventually Crumbles
Over a span of about four decades, countries within the Eastern Bloc would try to break free, and the Soviet Union would bring them back under control either through internal pressure, martial law or, as a last resort, military invasion. After a dispute between China and the Soviet Union, Albania -- which had established ties with China -- successfully left the Bloc in the early 1960s. Romania also made moves toward independence, including establishing diplomatic ties with West Germany, and in 1968, sweeping political reforms took place in Czechoslovakia, known as the "Prague Spring."
A military invasion of Czechoslovakia restored Communist rule in 1968, and when Poland later challenged its Communist Party for power, martial law kept the Bloc intact. Eventually, when Mikhail Gorbachev (1931– ) assumed power in 1985, his policies of openness and economic restructuring allowed the countries of the Eastern Bloc to adopt reforms and eventually to establish non-Communist governments. Gorbachev made it clear that he had no interest in forcing satellite countries in Eastern Europe to comply with Soviet control.
In 1989, the Eastern Bloc was considered to have finally and completely dissolved as the last Communist regime fell in Romania; Gorbachev pulled troops out of Afghanistan; and the Berlin wall was torn down.