

On June 22, 1941, Nazi Germany and its Axis allies began a massive invasion of the Soviet Union named Operation Barbarossa -- some 4.5 million troops launched a surprise attack deployed from German-controlled Poland, Finland, and Romania. Hitler had long had his eye on Soviet resources. Although Germany had signed a non-aggression pact with the USSR in 1939, both sides remained suspicious of one another, and the agreement merely gave them more time to prepare for a probable war. Even so, the Soviets were unprepared for the sudden blitzkreig attacks across a border that spanned nearly 2,900 km (1,800 mi), and they suffered horrible losses. Within a single week, German forces advanced 200 miles into Soviet territory, destroyed nearly 4,000 aircraft, and killed, captured, or wounded some 600,000 Red Army troops. By December of 1941, German troops were within sight of Moscow, and they laid siege to the city. But, when the notorious Russian winter (nicknamed "General Winter") set in, German advances came to a halt. By the end of this, one of the largest, deadliest military operations in history, Germany had suffered some 775,000 casualties. More than 800,000 Soviets had been killed, and an additional 6 million Soviet soldiers had been wounded or captured. Despite massive advances, Hitler's plan to conquer the Soviet Union before winter had failed, at great cost, and that failure would prove to be a turning point in the war. (This entry is Part 6 of a weekly 20-part retrospective of World War II)