WWII in Europe

1. Hitler believed that, based on the superiority in numbers and fighting technology on the aircraft, his Luftwaffe would defeat the Royal Air Force, no problem. 
2. Britain's victory in the Battle of Britain relied on the combination of multiple factors working together; however, I believe that Britain would not have succeeded, had they not been placed in the correct mindset to face Germany. With Churchill's speeches and radar technology British Soldiers, as well as civilians, were able to believe that they could defeat the German air forces. True, Germany also believed that they would win, but their mindset was prepared only for winning, and not for the possibility of defeat. Simply put, Germany got cocky and underestimated Britain's morale as well as the Royal Air Force. 
3. Mussolini failed to invade, so Hitler essentially invaded the Balkans himself to fix it. It is significant because not only was it a setback for the Allies, but also for Hitler as it set back his attack on the USSR by six weeks, placing the German Army in the Russian Winter.
4. Hitler wanted the lebensraum for German people, as well as the vast amount of natural resources that Russia had to offer. Also, Hitler wanted to destroy Communism and any Communists that he possibly could. And finally, Hitler wanted to put and end to Stalin's territorial gains. 
5. Weather conditions played a huge part, as German soldiers were not prepared for the heavy rains that muddied up the roads, nor for the harsh winter. German soldiers were not prepared for a long campaign or harsh conditions. And especially important, the sparse supplies to the German Army throughout had a devastating effect on them overall.