"The German invasion of Poland had begun"

German Army in Warsaw, 1939
Creative Commons Attribution Share AlikeGerman Army in Warsaw, 1939 - Credit: Deutsches Bundesarchiv
Hitler invaded Poland on 1 September 1939. Britain and France declared war on Germany two days later, after Hitler failed to heed a demand to call off the invasion.

By mid-October, Poland’s land had been divided between Germany, the Soviet Union, Slovakia and Lithuania.