On September 1, 1939, German forces staged a false-flag operation at Gleiwitz before launching a massive, unprovoked invasion of Poland under the codename Fall Weiss. Utilizing mechanized infantry, armored Panzer divisions, and Luftwaffe air power in an integrated doctrine later termed Blitzkrieg, the Wehrmacht shattered Polish border defenses and rapidly advanced toward Warsaw.
The invasion was rooted in Adolf Hitler's desire for Lebensraum in Eastern Europe and the revision of the Treaty of Versailles. Despite a secret non-aggression pact between Germany and the Soviet Union—the Molotov-Ribbentrop Pact—which partitioned Poland between them, Polish troops resisted fiercely at Westerplatte, Hel, and Warsaw.
The assault forced Britain and France to fulfill their defense guarantees, declaring war on Germany on September 3. On September 17, Soviet forces invaded Poland from the east, sealing the country's defeat and triggering World War II in Europe.
Why it matters
The invasion marked the official start of World War II in Europe after Allied powers abandoned appeasement. It demonstrated the devastating efficacy of modern combined-arms warfare, destroyed the interwar European security arrangement, and led directly to the brutal dual occupation and partition of Poland by Nazi Germany and the Soviet Union.
Interesting fact
The Polish defense of the Westerplatte peninsula lasted seven days against overwhelming odds, surprising German commanders who expected it to fall in hours.
People
- Edward Rydz-ŚmigłyCommander-in-Chief of Polish Armed Forces
- Adolf HitlerFührer and Chancellor of Nazi Germany
- Heinz GuderianCommander of XIX Army Corps pioneering armored tactics
Quotes
"This night regular German troops invaded our territory. I ask you all to remain calm."
Gallery
Location
Westerplatte Peninsula · Gdańsk · Poland
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