Nazi Germany terminated the Molotov–Ribbentrop Pact at 03:15 on 22 June 1941 by launching a massive attack on the Soviet positions in eastern Poland which marked the beginning of the invasion of the Soviet Union known as Operation Barbarossa. Stalin had ignored several warnings that Germany was likely to invade, and ordered no 'full-scale' mobilization of forces although the mobilization was ongoing. After the launch of the invasion, the territories gained by the Soviet Union as a result of the Molotov–Ribbentrop Pact were lost in a matter of weeks. Within six months, the Soviet military had suffered 4.3 million casualties, and Germany had captured three million Soviet prisoners. The lucrative export of Soviet raw materials to Nazi Germany over the course of the Nazi–Soviet economic relations (1934–41) continued uninterrupted until the outbreak of hostilities. The Soviet exports in several key areas enabled Germany to maintain its stocks of rubber and grain from the first day of the invasion until October 1941.

Where did the German attack on Soviet forces occur?