Origins of the Cold War

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History of the Cold War

The Origins of the Cold War are widely regarded to lie most directly in the relations between the Soviet Union and the allies (the United States, Great Britain and France) in the years 1945–1947. Those events led to the Cold War that endured for just under half a century.

Events preceding the Second World War, and even the Russian Revolution of 1917, underlay pre–World War II tensions between the Soviet Union, western European countries and the United States. A series of events during and after World War II exacerbated tensions, including the Soviet-German pact during the first two years of the war leading to subsequent invasions, the perceived delay of an amphibious invasion of German-occupied Europe, the western allies' support of the Atlantic Charter, disagreement in wartime conferences over the fate of Eastern Europe, the Soviets' creation of an Eastern Bloc of Soviet satellite states, western allies scrapping the Morgenthau Plan to support the rebuilding of German industry, and the Marshall Plan.

In World War I, the US, Britain, and Russia had been allies for seven months, from April 1917 until the Bolsheviks seized power in Russia in November. In 1918, the Bolsheviks negotiated a separate peace with the Central Powers at Treaty of Brest-Litovsk. This separate peace contributed to American mistrust of the Soviets, since it left the Western Allies to fight the Central Powers alone.

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