 Complete the following phrase:  On 22 June 1941, contravening the MolotovRibbentrop Pact of 1939, over three million Axis troops attacked the Soviet Union. This offensive codenamed Operation Barbarossa was intended to destroy the Soviet Union and seize its natural resources for subsequent aggression against the Western powers. The invasion conquered a huge area, including the Baltic republics, Belarus, and West Ukraine. By early August, Axis troops had advanced and won the Battle of Smolensk. Hitler ordered Army Group Centre to temporarily halt its advance to Moscow and divert its Panzer groups to aid in the encirclement of Leningrad and 