The Nazi-Soviet pact, or the non-aggression pact.
Stalin did not needed Hitler for help. They were not allies during World War II. They became enemies after Hitler violated a non-aggression pact. Yes, with the exception of the division of Poland and the Soviet occupation of the Baltic states there was nothing in common between the two. The non aggression pact was used by Hitler to secure his eastern frontier prior to launching Barbarossa in the summer of 1941.
They wanted all part of the same thing nation.
Albania
The Soviet Union (Russia) joined the Allies in World War II after Germany abrogated the Molotov-Ribbentrop Pact (1939), invading Russia, the Ukraine, the Baltic States, and Russian-occupied Poland. The initial operation, Operation Barbarossa, began on June 22, 1941.
Japan
Japan
Japan violated the Kellogg-Briand pact in 1931. The pact stated that war would not be used to resolve conflicts.
Germany.
Kellogg-Briand Pact did not prevent U.S. intervention in Central America , the Japanese invasion of Manchuria in 1931 , the Italian invasion of Abyssinia in 1935 and the German and Soviet Union invasions of Poland .
The Molotov Pact: a non aggression agreement which was eventually violated by Germany when they invaded Russia.
The German invasion of Russia was the result .
The Russo-German Non-Aggression Pact was first violated by Adolf Hitler, although it is unlikely that Stalin or Hitler ever intended on keeping the pact throughout the entirety of the war. Their extremely opposite ideologies would have prevented this.
Kellogg-Briand Pact
Non abiding pact
Adolf Hitler (Germany) and Josef Stalin (Soviet Union) created a pact not to go to war with each other. Adolf Hitler violated this pact when he invaded the Soviet Union.
5 March, 1931