Nazi Germany and Soviet Union Sign Non-Aggression Pact
In the summer of 1939, as Nazi Germany prepared to invade Poland amid failed negotiations with Britain and France, Adolf Hitler sought to neutralize the Soviet threat on his eastern flank. Soviet leader Joseph Stalin, wary of Western powers after the Munich Agreement and seeking territorial security, authorized secret talks. On August 23, 1939, in Moscow, German Foreign Minister Joachim von Ribbentrop and Soviet Foreign Minister Vyacheslav Molotov signed the Treaty of Non-Aggression, publicly committing both nations to ten years of peace and neutrality. A secret protocol divided Eastern Europe into spheres of influence, assigning Poland, the Baltic states, Finland, and parts of Romania to German or Soviet control. The pact enabled Germany's September 1 invasion of Poland, triggering World War II.
Why it matters: The agreement allowed Hitler to fight a two-front war avoided in 1914, facilitating rapid conquests in the west before turning east in 1941, while enabling Stalin's annexations that reshaped Eastern European borders for decades. It exemplified cynical great-power diplomacy that prioritized short-term gains over ideology, leading to the war's outbreak and long-term Cold War divisions in Europe.