Germany broke its pact with the Soviet Union and invaded there, but the winter and Soviet counterattack killed many German troops.
The year 1941 was one of escalation around the world. Italy may have been defeated in Greece, but that didn't mean that Germany wouldn't take the country. Then it was on to Yugoslavia and Russia. Germany broke its pact with the Soviet Union and invaded there, but the winter and Soviet counterattack killed many German troops. The Soviets next joined the Allies. Within a week of the Pearl Harbor attack, Japan had invaded Burma, Hong Kong (then under British control), and the Philippines, and the United States was officially in the conflict.