This Day In History: The German Invasion of Poland

This day marks the anniversary of Nazi Germany's 1939 invasion of Poland. Although Japan and China had seen fighting since 1931 (and had begun total warfare in 1937), it was Germany's act of aggression that is generally considered to be the start of World War II. Two days after the invasion, on September 3, France and Britain declared war on Germany. The Soviet Union, which had entered into a non-aggression pact with Germany on August 23, 1939, invaded Poland's eastern borders on September 17.

October 5, 1939: Hitler and the German army in Warsaw

Fighting in Poland continued until October 6, 1939 when Germany and the Soviets fully controlled Poland. Unlike France, which was defeated by Germany in June of the following year, Poland never officially surrendered.