Molotov–Ribbentrop Pact

The 1939 nonaggression treaty between Nazi Germany and the Soviet Union, accompanied by secret protocols assigning parts of Eastern Europe to their spheres of influence.

Secret Protocols of the Molotov–Ribbentrop Pact: Confidential agreements that assigned Eastern European territories to German and Soviet spheres of influence. They mapped the territorial division omitted from the pact’s public text.
German–Polish Non-Aggression Pact: A 1934 agreement in which Germany and Poland pledged to resolve disputes without force. Its collapse preceded Germany’s turn toward an agreement with the Soviet Union.
Invasion of Poland: Germany’s invasion of Poland on September 1, 1939, which began the Second World War in Europe. The pact removed the immediate risk of a Soviet-German conflict as Germany attacked Poland.
Collective security: A policy in which states cooperate to deter or resist aggression against any member. The bilateral pact replaced a Soviet effort to build broader security against German expansion.
German–Soviet Boundary and Friendship Treaty: A September 1939 agreement that revised the German–Soviet partition line in occupied Poland. It formalized the new boundary after Germany and the Soviet Union invaded Poland.
Munich Agreement: A 1938 agreement allowing Nazi Germany to annex the Sudetenland from Czechoslovakia. The failure of collective security after Munich shaped Soviet distrust of Britain and France.
Soviet invasion of Poland: The Soviet Union’s invasion of eastern Poland, beginning September 17, 1939. It carried out the pact’s agreed division of Polish territory.
Anti-Comintern Pact: A 1936 agreement between Germany and Japan opposing the Communist International. Its anti-communist purpose highlights the ideological reversal behind the 1939 pact.
German–Soviet Commercial Agreement: A series of agreements that exchanged Soviet raw materials for German industrial goods and technology. Trade arrangements supplied Germany with resources during its war against Britain and France.
Anglo-Soviet-French negotiations of 1939: Tripartite talks seeking a security agreement among Britain, France, and the Soviet Union. Their failure left Stalin pursuing an agreement with Hitler instead.

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