In the late 1920s and early 1930s, Stalin reversed the Bolshevik agrarian policy by seizing land given earlier to the peasants and organizing collective farms. This essentially reduced the peasants back to serfs, as they had been during the monarchy.
As war clouds rose over Europe in 1939, Stalin made a seemingly brilliant move, signing a nonaggression pact with Germany's Adolf Hitler and his Nazi Party. Stalin was convinced of Hitler's integrity and ignored warnings from his military commanders that Germany was mobilizing armies on its eastern front. When the Nazi blitzkrieg struck in June 1941, the Soviet Army was completely unprepared and immediately suffered massive losses.
To make matters worse, the purges of the 1930s had depleted the Soviet Army and government leadership to the point where both were nearly dysfunctional. After heroic efforts on the part of the Soviet Army and the Russian people, the Germans were turned back at the Battle of Stalingrad in 1943. By the next year, the Soviet Army was liberating countries in Eastern Europe, even before the Allies had mounted a serious challenge against Hitler at D-Day.
As the tide of war slowly turned in the Allies' favor, Roosevelt and Churchill met with Joseph Stalin to discuss postwar arrangements. At the first of these meetings, in Tehran, Iran, in late 1943, the recent victory in Stalingrad put Stalin in a solid bargaining position. He demanded the Allies open a second front against Germany, which they agreed to in the spring of 1944.
Earlier, he had ordered the Soviet representative to the United Nations to boycott the Security Council because it refused to accept the newly formed Communist People's Republic of China into the United Nations. When the resolution to support South Korea came to a vote in the Security Council, the Soviet Union was unable to use its veto.
Though his popularity from his successes during World War II was strong, Stalin's health began to deteriorate in the early 1950s. After an assassination plot was uncovered, he ordered the head of the secret police to instigate a new purge of the Communist Party. Before it could be executed, however, Stalin died on March 5, 1953. He left a legacy of death and horror.