The cold war was the time of rivalry and conflict between the USA and the Soviet Union. It was a time of political tension, in which both superpowers tried to prevent each other from gaining too much power.
After World War II. Although the United States and the Soviet Union were allies during World War II, they had different ideas about the future of the world. In 1949 the United States and other western countries founded NATO (the North Atlantic Treaty Organization), on the other side the soviets led the Warsaw Pact, a military organization of eastern European countries. Two of the major events of the cold War took place in Berlin. After World War II the city was divided into four zones.