World War II was fought between two major groups of nations. They became known as the Axis and Allied Powers. The major Allied Powers were Britain, France, Russia, and the United States.The Allies formed mostly as a defense against the attacks of the Axis Powers. The original members of the Allies included Great Britain, France and Poland. When Germany invaded Poland, Great Britain and France declared war on Germany. Russia becomes and Ally At the start of World War II, Russia and Germany were friends. However, on 22 June 1941 Hitler, the leader of Germany, ordered a surprise attack on Russia. Russia then became an enemy of the Axis Powers and joined the Allies. The US Joins the Allied Powers The United States had hoped to remain neutral during
