World War II (United States)

World War II began in September 1939 when Germany attacked Poland and began a campaign to occupy much of Central Europe. The US maintained neutrality in the war until the Japanese bombing of Pearl Harbor, Hawaii, on December 7, 1941. One day later, President Theodore Roosevelt asked Congress to declare war on Japan, after which Germany and Italy declared war on the United States. The war would continue in Europe and the Pacific for four more years, ending with Japan’s surrender in September 1945. Before the Allies declared victory, nearly 420,000 US military and civilian lives were lost.