Joseph Stalin (1879-1953) led the Communist Party and ruled the Soviet Union from 1924 until his death in 1953. Stalin became a Bolshevik in 1903, and took control following the death of Soviet leader Vladimir Lenin in 1924. In the 1930s, he conducted bloody purges of all rivals to his authority, and launched a series of ruthless Five-Year Plans to rapidly industrialize the country. In August 1939, Stalin approved the Molotov-Ribbentrop Pact between the Soviet Union and Germany, which divided Poland and eastern Europe into German and Soviet spheres of influence.
When Germany invaded the Soviet Union in 1941, Stalin was taken completely by surprise. Nevertheless, he rallied the country against the Germans and, under his leadership, the Soviet Union played a critical role in defeating the Axis powers. After the war, Stalin quickly cemented Soviet control over eastern Europe, a policy which led to the beginning of the Cold War.
