Answer:
The Soviet Union signed a non-aggression pact with Germany and later on joined the allies.
Step-by-step explanation:
On August 23rd, 1939, shortly after the Second World War had begun, Nazi Germany and the Soviet Union surprised the rest of the world by signing a non-aggression pact. The pact, who was signed by foreign ministers Joachim Von Ribbentrop and Vyacheslav Molotov, stated that both countries agreed to take no military action against each other for the following 10 years and that neither of the nations would aid external countries that attack either Germany or the soviet Union.
On June 22nd, 1941, German troops invaded the Soviet Union and as a response to such action, The Soviet Union joined the Allies against Germany.