Although Hitler was apparently surprised when France and Britain declared war on September 3, he was confident of ultimate victory. After a winter of waiting (called the “phony war”), on April 9, 1940, Germany launched a Blitzkrieg against Denmark and Norway. One month later, the Germans attacked the Netherlands, Belgium, and France. German panzer divisions broke through the weak French defensive positions in the Ardennes forest and raced across northern France, splitting the Allied armies and trapping French troops and the entire British army on the beaches of Dunkirk. Only by heroic efforts did the British succeed in a gigantic evacuation of 330,000 Allied (mostly British) troops. The French capitulated on June 22. German armies occupied about three-fifths of France while the French hero of World War I, Marshal Philippe Pétain (1856 –1951), established a puppet regime (known as Vichy France) over the remainder. Germany was now in control of western and central Europe (see Map 6.1). Britain had still not been defeated, but it was reeling, and the wartime cabinet under Prime Minister Winston Churchill debated whether to seek a negotiated peace settlement. As Hitler realized, an amphibious invasion of Britain could succeed only if Germany gained control of the air. In early August 1940, the Luftwaffe (German air force) launched a major offensive against British air and naval bases, harbors, communication centers, and war industries. The British fought back doggedly, supported by an effective radar system that gave them early warning of German attacks. Nevertheless, the British air force suffered critical losses and was probably saved by Hitler’s change in strategy. In September, in retaliation for a British attack on Berlin, Hitler ordered a shift from military targets to massive bombing of cities to break British morale. The British rebuilt their air strength quickly and were soon inflicting major losses on Luftwaffe bombers. By the end of September, Germany had lost the Battle of Britain, and the invasion of the British Isles had to be abandoned. At this point, Hitler pursued a new strategy, which would involve the use of Italian troops to capture Egypt and the Suez Canal, thus closing the Mediterranean to British ships and thereby shutting off Britain’s supply of oil. This strategy failed when the British routed the Ital- ian army. Although Hitler then sent German troops to the North African theater of war, his primary concern lay elsewhere; he had already reached the decision to fulfill his long-time obsession with the acquisition of territory in the east. In Mein Kampf, Hitler had declared that future German expansion must lie in the east, in the vast plains of southern Russia. Hitler was now convinced that Britain was remaining in the war only because it expected Soviet support. If the Soviet Union were smashed, Britain’s last hope would be eliminated. Moreover, the German general staff was convinced that the Soviet Union, whose military leadership had been decimated by Stalin’s purge trials, could be defeated quickly and decisively. The invasion of the Soviet Union was scheduled for spring 1941 but was delayed because of problems in the Balkans. Mussolini’s disastrous invasion of Greece in October 1940 exposed Italian forces to attack from British air bases in that country. To secure their Balkan flank, German troops seized both Yugoslavia and Greece in April 1941. Hitler had already obtained the political cooperation of Hungary, Bulgaria, and Romania. Now reassured, Hitler ordered an invasion of the Soviet Union on June 22, 1941, in the belief that the Soviets could still be decisively defeated before winter set in. It was a fateful miscalculation. The massive attack stretched out along an 1,800-mile front. German troops, supported by powerful panzer units, advanced rapidly, capturing two million Russian soldiers. By November, one German army group had swept through Ukraine and a second was besieging Leningrad; a third approached within 25 miles of Moscow, the Russian capital. An early winter and unexpected Soviet resistance, however, brought a halt to the German advance. For the first time in the war, German armies had been stopped. A counterattack in December 1941 by Soviet army units newly supplied with U.S. weapons came as an ominous ending to the year for the Germans.