Molotov–Ribbentrop Pact

The situation reached a general crisis in late August as German troops continued to mobilize against the Polish border. On 23 August, when tripartite negotiations about a military alliance between France, the United Kingdom and Soviet Union stalled, the Soviet Union signed a non-aggression pact with Germany. The Treaty of Non-Aggression between Germany and the Union of Soviet Socialist Republics was a non-aggression pact between Nazi Germany and the Soviet Union that enabled those two powers to divide-up Poland between them.