Overview and main developments of the historical Cold War After World War II, the world split into a capitalist camp centered on the United States and a socialist camp centered on the Soviet Union. Both camps avoided direct war but clashed in various regions around the globe. The United States rallied Western nations through NATO and other alliances, while the Soviet Union brought Eastern European countries under its sphere of influence. In the 1950s, the Korean War and the nuclear arms race intensified the rivalry. By the 1960s, the Cuban Missile Crisis brought tensions to the brink of nuclear war. Subsequently, proxy wars such as the Vietnam War continued, even as U.S.-Soviet relations began to ease. From the late 1970s onward, tensions escalated once again. In the 1980s, economic stagnation in the Soviet Union and the invasion of Afghanistan weakened the socialist bloc. Following Mikhail Gorbachev’s reforms and the Eastern European revolutions, the Berlin Wall fell in 1989. With the dissolution of the Soviet Union in 1991, the Cold War came to an end.