In the summer of 1940, as German armies rolled across the West, Soviet troops entered the Baltic states of Estonia, Latvia, and Lithuania. Preoccupied with crushing Britain, Hitler took no action in the Baltics or elsewhere in Eastern Europe, but his thoughts soon turned to Stalin and Bolshevism. Even as the Luftwaffe battled the Royal Air Force in the skies over Britain, Hitler ordered his commanders to make preparations for a massive invasion of the Soviet Union.

On November 12, 1940, Soviet Foreign Minister Molotov arrived in Berlin to discuss, in effect, dividing up the spoils of a war the Nazis believed was already won. Molotov drove such a hard bargain that Ribbentrop and even Hitler found themselves on the defensive. The encounter with Molotov reinforced Hitler’s determination to crush the Soviet Union, though for the time being he continued to feign friendship with the Soviets. Meanwhile, frustrations mounted. Mussolini’s armies suffered an embarrassing defeat in Greece, prompting Hitler to turn his attention to the troublesome Balkans, where an anti-Nazi uprising among the Serbs in Yugoslavia so enraged Hitler that he made what Shirer calls “the most fateful decision of all” and “probably the most catastrophic single decision in Hitler’s career” (824).