Invasion of Poland 1939

The invasion of Poland, which began on September 1, 1939, marked the start of World War II. It was a joint military campaign by Nazi Germany and the Soviet Union, following their non-aggression pact signed in August 1939. Germany attacked from the west, utilizing Blitzkrieg tactics, while the Soviet Union invaded from the east on September 17. The rapid and overwhelming attacks led to the swift collapse of Polish defenses, and by the end of September, Poland was divided between the two invading powers. This invasion prompted Britain and France to declare war on Germany, marking the official beginning of the global conflict.