The Cold War split the temporary wartime alliance against Nazi Germany, leaving the Soviet Union and the United States as two superpowers with profound economic and political differences. The USSR was a Marxist–Leninist state led by its Communist Party, which in turn was dominated by a leader with different titles over time, and a small committee called the Politburo. The Party controlled the press, the military, the economy and many organizations. It also controlled the other states in the Eastern Bloc, and funded Communist parties around the world, sometimes in competition with Communist China, particularly following the Sino-Soviet split of the 1960s. In opposition stood the capitalist West, led by the United States, a federal republic with a two-partypresidential system. The First World nations of the Western Bloc were generally liberal democratic with a free press and independent organizations, but were economically and politically entwined with a network of banana republics and other authoritarian regimes throughout the Third World, most of which were the Western Bloc's former colonies. Some major Cold War frontlines such as Vietnam, Indonesia, and the Congo were still Western colonies in 1947.
The first phase of the Cold War began in the first two years after the end of the Second World War in 1945. The USSR consolidated its control over the states of the Eastern Bloc, while the United States began a strategy of global containment to challenge Soviet power, extending military and financial aid to the countries of Western Europe (for example, supporting the anti-communist side in the Greek Civil War) and creating the NATO alliance. The Berlin Blockade (1948–49) was the first major crisis of the Cold War. With the victory of the communist side in the Chinese Civil War and the outbreak of the Korean War (1950–53), the conflict expanded. The USSR and the USA competed for influence in Latin America and the decolonizing states of Africa and Asia. The Hungarian Revolution of 1956 was stopped by the Soviets. The expansion and escalation sparked more crises, such as the Suez Crisis (1956), the Berlin Crisis of 1961, and the Cuban Missile Crisis of 1962. Meanwhile, an international peace movement took root and grew among citizens around the world, first in Japan from 1954, when people became concerned about nuclear weapons testing, but soon also in Europe and the US. The peace movement, and in particular the anti-nuclear movement, gained pace and popularity from the late 1950s and early 1960s, and continued to grow through the 70s and 80s with large protest marches, demonstrations and various non-parliamentary activism opposing war and calling for global nuclear disarmament. Following the Cuban Missile Crisis, a new phase began that saw the Sino-Soviet split complicate relations within the communist sphere, while US allies, particularly France, demonstrated greater independence of action. The USSR crushed the 1968 Prague Spring liberalization program in Czechoslovakia, and the Vietnam War (1955–75) ended with the defeat of the US-backed Republic of Vietnam, prompting further adjustments.
The Cold War and its events have left a significant legacy. It is often referred to in popular culture, especially in media featuring themes of espionage (notably the internationally successful James Bond book and film franchise) and the threat of nuclear warfare. Meanwhile, a renewed state of tension between the Soviet Union’s successor state, Russia, and the United States in the 2010s (including its Western allies) has been referred to as the Second Cold War.
At the end of World War II, English writer George Orwell used cold war, as a general term, in his essay "You and the Atomic Bomb", published 19 October 1945 in the British newspaper Tribune. Contemplating a world living in the shadow of the threat of nuclear warfare, Orwell looked at James Burnham's predictions of a polarized world, writing:
Looking at the world as a whole, the drift for many decades has been not towards anarchy but towards the reimposition of slavery... James Burnham's theory has been much discussed, but few people have yet considered its ideological implications—that is, the kind of world-view, the kind of beliefs, and the social structure that would probably prevail in a state which was at once unconquerable and in a permanent state of "cold war" with its neighbours.
In The Observer of 10 March 1946, Orwell wrote, "after the Moscow conference last December, Russia began to make a 'cold war' on Britain and the British Empire."
The first use of the term to describe the specific post-war geopolitical confrontation between the USSR and the United States came in a speech by Bernard Baruch, an influential advisor to Democratic presidents, on 16 April 1947. The speech, written by journalist Herbert Bayard Swope, proclaimed, "Let us not be deceived: we are today in the midst of a cold war." Newspaper columnist Walter Lippmann gave the term wide currency with his book The Cold War; when asked in 1947 about the source of the term, Lippmann traced it to a French term from the 1930s, la guerre froide.