Allies

A coalition of countries that fought against the Axis powers during World War II. The principal members of the Allies were Great Britain, the Soviet Union, the United States, and China, as well as France.

Great Britain and France entered the war against Germany on September 3, 1939, two days after the Nazi invasion of Poland. They were joined by Denmark and Norway when Germany invaded both countries on April 9, 1940. Belgium, the Netherlands, and Luxembourg aligned with the Allies in May 1940, but soon fell under Nazi occupation. Similarly in southeastern Europe, Greece and Yugoslavia joined the Allies on October 28, 1940, and April 6, 1941, respectively, but were soon occupied by Axis powers.

France surrendered to Nazi forces in June 1940, leaving Great Britain as the only Allied power actively fighting the war for a year. The Nazi invasion of the Soviet Union in June 1941 resulted in a treaty between Britain and the U.S.S.R. Unlike the smaller European nations that were swiftly conquered by Germany, the Soviet Union proved capabable of withstanding the Nazi attack and eventually drove German forces back to Berlin.

Following the Japanese attack on Pearl Harbor on December 7, 1941 , the United States entered the war on the side of the Allies.