The aftermath of World War II was the beginning of an era defined by the decline of all great powers except for the Soviet Union and the United States, and the simultaneous rise of the two superpowers. Allies during World War II, the USA and the USSR became competitors on the world stage and engaged in the Cold War, so called because it never resulted in overt, declared hot war between the two powers but was instead characterized by espionage, political subversion and proxy wars. Western Europe and Japan were rebuilt through the American Marshall Plan whereas Eastern Europe fell under the Soviet sphere of influence and eventually an "Iron Curtain". Europe was divided into a US-led Western Bloc and a Soviet-led Eastern Bloc. Internationally, alliances with the two blocs gradually shifted, with some nations trying to stay out of the Cold War through the Non-Aligned Movement. The Cold War also saw a nuclear arms race between the two superpowers; part of the reason that the Cold War never became a "hot" war was that the Soviet Union and the United States had nuclear deterrents against each other, leading to a mutually assured destruction standoff.
As a consequence of the war, the Allies created the United Nations, an organization for international cooperation and diplomacy, similar to the League of Nations. Another result was increased the rate of decolonization from the great powers with independence being granted to India (from the United Kingdom), Indonesia (from the Netherlands), the Philippines (from the US) and a number of Arab nations. It also saw the rise of communist influence in Southeast Asia, with the People's Republic of China, as the Chinese Communists emerged victorious from the Chinese Civil War in 1949.