USA HISTORY

Detailed explanation-1: -World War II the chief Allied powers were Great Britain, France (except during the German occupation, 1940–44), the Soviet Union (after its entry in June 1941), the United States (after its entry on December 8, 1941), and China.

Detailed explanation-2: -The Soviet Union, which initially had a nonaggression pact with Germany and participated in its invasion of Poland, joined the Allies in June 1941 after Operation Barbarossa, the German invasion of the Soviet Union.

Detailed explanation-3: -When World War II started, the Soviet Union was effectively an ally of Nazi Germany in a relatively conventional European interstate war. Although the Germans did most of the fighting in Poland, the Soviet Union occupied the eastern part.

Detailed explanation-4: -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.