The war map gave Adolf Hitler every reason to be confident. Operation Barbarossa, Germany's invasion of the Soviet Union begun on June 22, 1941, had succeeded spectacularly on nearly every front. One Soviet army after another had been smashed as Germany's Ostheer, its army in the East, plunged deep into the industrial heart of Josef Stalin's vast Eurasian state. By September, Hitler's legions were within sight of Leningrad, while to the south German and Romanian divisions had swept across the north shores of the Black Sea, threatening vital petrochemical and agricultural production within the vulnerable Ukraine and Crimean regions.
Between the two sectors, Army Group Center, under Field Marshal Fedor von Bock, had taken 610,000 prisoners and destroyed 5,700 enemy tanks. Bock's soldiers had conquered land as far eastward as the Russian city of Smolensk and were now less than 180 miles from the Soviet capital.