The outbreak of World War II took place in Poland, and for many months a "phony war" was waged, which seemed of little direct importance to Britain and France. Then suddenly in the spring of 1940, the Germans unleashed a blitzkrieg through neutral Belgium, outflanking the Maginot Line and driving the British in confusion to the English Channel, where only the miracle of Dunkirk prevented their annihilation.
Hitler`s plan was to invade England, but he began with an air assault designed to soften the country up. To his surprise, the British fought back and the Royal Air Force (RAF) fought the Germans to a draw in the Battle of Britain during the summer. Eventually, Hitler changed his mind and decided to dispatch the Soviet Union first. His invasion of the USSR in the summer of 1941 relieved the immediate threat to Britain.
After ousting the Nazis from North Africa, the Allies conducted their first operations on the European mainland when they invaded Italy. This was just a prelude, however, to the main attack, which took place on D-Day, June 5, 1944, when the combined forces of Canadian, American, and British troops landed at Normandy.
The allies were successful in establishing and expanding their beachhead, then in advancing to Paris, which was liberated on August 25. The allies growing confidence in their ability to handle any Nazi attack was badly tested in the Battle of the Bulge at Christmas, 1944. The German advance was halted and from that point until the final surrender on May 5, 1945, the Allies continuously pushed the Germans troops back, first to the border and then deeper into Germany itself.