At dawn on September 1, 1939, the Germans launched their land, air, and sea assault on Poland, sparking the great conflagration of World War II and shocking the world with the speed and ferocity of their blitzkrieg. With thundering panzers and screaming dive-bombers, they crushed the vital port of Danzig into submission, drove the Polish Air Force from the skies, and took Warsaw amid great bloodshed. After six weeks of brave resistance, the Poles surrendered, no match for the Nazi war machine.