On 22 June 1941, Nazi Germany broke the Molotov–Ribbentrop Pact; and invaded the ill-prepared Soviet Union with the largest and most powerful invasion force in human history, opening the largest theater of World War II. The German Hunger Plan foresaw the starvation and extinction of a great part of the Soviet population, and Generalplan Ost called for the elimination of over 70 million Russians for Lebensraum.