Origins of the Cold War

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History of the Cold War
Origins World War II Hiroshima and Nagasaki Aftermath Eastern Bloc Western Bloc Iron Curtain
Periods Cold War (1947–1948) Cold War (1948–1953) Cold War (1953–1962) Cold War (1962–1979) Cold War (1979–1985) Cold War (1985–1991) Frozen conflicts
Related topics Timeline of events Historiography Related conflicts Post–Cold War era Relations since 1989 Second Cold War Post-Soviet conflicts Arab Cold War Cold War in Asia Reagan Doctrine
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The Cold War emerged from the breakdown of relations between two of the primary victors of World War II: the United States and Soviet Union, along with their respective allies in the Western Bloc and Eastern Bloc. This ideological and political rivalry, which solidified between 1945-49, would shape the global order for the next four decades.

The roots of the Cold War can be traced back to diplomatic and military tensions preceding World War II. The 1917 Russian Revolution and the subsequent Treaty of Brest-Litovsk, where Soviet Russia ceded vast territories to Germany, deepened distrust among the Western Allies. Allied intervention in the Russian Civil War further complicated relations, and although the Soviet Union later allied with Western powers to defeat Nazi Germany, this cooperation was strained by mutual suspicions.

In the immediate aftermath of World War II, disagreements about the future of Europe, particularly Eastern Europe, became central. The Soviet Union's establishment of communist regimes in the countries it had liberated from Nazi control—enforced by the presence of the Red Army—alarmed the US and UK. Western leaders saw this as a clear instance of Soviet expansionism, clashing with their vision of a democratic Europe. Economically, the divide was sharpened with the introduction of the Marshall Plan in 1947, a US initiative to provide financial aid to rebuild Europe and prevent the spread of communism by stabilizing capitalist economies. The Soviet Union rejected the Marshall Plan, seeing it as an effort by the US to impose its influence on Europe. In response, the Soviet Union established Comecon (Council for Mutual Economic Assistance) to foster economic cooperation among communist states.

The first major military confrontation of the Cold War came with the Berlin Blockade of 1948–49, when the Soviets attempted to cut off Western access to Berlin. The US and its allies responded with the Berlin Airlift, supplying West Berlin by air. This marked a turning point, shifting the Cold War from diplomatic tensions to the brink of direct military conflict, further entrenching the division of Europe. By 1949, the Cold War was firmly in place.^[1] The creation of NATO in 1949 formalized military alliances within the Western Bloc, signaling the start of a long period of geopolitical confrontation.