Invasion of Poland, attack on Poland by Nazi Germany that marked the start of World War II. The invasion lasted from September 1 to October 5, 1939.

　　As dawn broke on September 1, 1939, German forces launched a surprise attack on Poland. The attack was sounded with the predawn shelling, by the German battleship Schleswig-Holstein, of Polish fortifications at the Baltic port of Danzig (modern Dansk). Sixty-two divisions, with more than 1,300 airplanes in support, then commenced a coordinated assault across the German–Polish border. Army Group North attacked from Pomerania and East Prussia, while Army Group South drove deep into southern Poland from Silesia and Slovakia. Strategically outflanked and materially outnumbered, Polish forces stood little chance, especially because they were deployed too close to the German frontier, unintentionally facilitating Germany’s strategy of envelopment.

　　World War II Events keyboard_arrow_left

　　Holocaust 1933 - 1945

　　Invasion of Poland September 1, 1939 - October 5, 1939

　　Battle of the Atlantic September 3, 1939 - May 8, 1945

　　Dunkirk evacuation May 26, 1940 - June 4, 1940

　　North Africa campaigns June 1940 - May 13, 1943

　　Battle of Britain July 1940 - September 1940

　　Vichy France July 1940 - September 1944

　　the Blitz September 7, 1940 - May 11, 1941

　　Battle of Crete May 20, 1941 - June 1, 1941

　　Operation Barbarossa June 22, 1941

　　Battle of Moscow September 30, 1941 - January 7, 1942

　　Pearl Harbor attack December 7, 1941

　　Battle of Wake Island December 8, 1941 - December 23, 1941

　　Pacific War December 8, 1941 - September 2, 1945

　　Bataan Death March April 9, 1942

　　Kokoda Track Campaign July 1942 - January 1943

　　Battle of Stalingrad August 22, 1942 - February 2, 1943

　　Warsaw Ghetto Uprising April 19, 1943 - May 16, 1943

　　Operation Fortitude 1944

　　Normandy Invasion June 6, 1944 - July 9, 1944

　　Battle of Saipan June 15, 1944 - July 9, 1944

　　Operation Bagration June 23, 1944 - August 19, 1944

　　Cowra breakout August 5, 1944

　　Operation Market Garden September 17, 1944 - September 27, 1944

　　Battle of the Bulge December 16, 1944 - January 16, 1945

　　Yalta Conference February 4, 1945 - February 11, 1945

　　Battle of Iwo Jima February 19, 1945 - March 26, 1945

　　Battle for Castle Itter May 5, 1945

　　atomic bombings of Hiroshima and Nagasaki August 6, 1945 - August 9, 1945 keyboard_arrow_right The powerful Luftwaffe destroyed the Polish air force in days, leaving the Polish army at the mercy of the German panzer divisions. The speed with which the German tank units cut through the Polish lines was to give a new name to the lexicon of warfare: blitzkrieg (“lightning war”). The declaration of war on Nazi Germany by Britain and France on September 3 did nothing to help Poland.

　　The Poles enjoyed a limited tactical success from September 9 to 15 at the Bzura River, yet it came to nothing as the German armies closed in on Warsaw. Poland’s fate had already been sealed, when—in accordance with the secret terms of the Nazi-Soviet pact—the Red Army crossed the Polish border from the east on September 17. Warsaw and a few garrisons continued to hold out briefly but eventually surrendered. Poland was divided between Nazi Germany and the Soviet Union.

　　Before the invasion began, Adolf Hitler’s general staff worried that the assault was premature because the army (Wehrmacht) was not yet at full strength and that victory could not be assured, The invasion was thus a highly calculated risk, one that Hitler was so willing to take that it was originally scheduled to begin a week earlier. The attack on Poland was an initial victory for Germany that surpassed the staff’s initial expectations, but it also galvanized Polish military resistance with the formation of a strong partisan underground that would never flag during the course of World War II and a Polish army in exile that would fight alongside the Allies at major engagements that included Operation Market Garden and the Battle of Monte Cassino.

　　In the end, German losses totaled 14,000 dead or missing and 30,000 wounded out of a total of 1,250,000 troops involved in the invasion; Polish casualties numbered 66,000 dead, 130,000 wounded, and 400,000 captured out of 800,000 troops.

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