Once its system of satellite states was built up after World War II, Eastern Europe (and, for some time, China) was the area of most concern to the Soviet Union. With the United States and the Western alliance, relations were marked by alternating episodes of crisis and cooperation. An innovation of the post-Stalin years was the widening of contacts with the developing nations of the Third World, which Moscow saw as fertile ground for extension of its military, political, and economic influence.

Soviet military and political relations with its satellite states in Eastern Europe were mainly bilateral until the mid-1950s. Formation of the Warsaw Pact in 1955 gave the Soviet bloc a counterpart to NATO, increased military coordination, and provided a forum in which wider political issues could be considered. Cominform, founded in 1947 in an attempt to impose political uniformity on friendly states and movements, was disbanded in April 1956. East Germany (the German Democratic Republic, or GDR), constituted as a sovereign state in 1949, remained of special concern to Moscow. In June 1953 Soviet troops helped put down a rebellion of workers in East Berlin. The status of Berlin, where the border between the two German states was open, became a more hotly contested issue as West German prosperity induced hundreds of thousands of East Germans to flee through the divided city. In August 1961 the Soviet Union and the East German government built the infamous Berlin Wall, which prevented East Germans from freely emigrating to the West.