This document provides background information on the rise of totalitarian regimes in Europe and Asia in the 1930s, including the regimes led by Joseph Stalin in the Soviet Union, Benito Mussolini in Italy, and Adolf Hitler in Germany. It then discusses the early years of World War II, including Germany's rapid military conquests across Europe in 1939-1941. It also covers the debate in the United States over intervention in the war prior to the Japanese attack on Pearl Harbor in 1941, which prompted America's entry into the war. Finally, it summarizes the initial challenges faced by the Allies in 1942 as Japan expanded its territory rapidly in the Pacific.