How did Germany conquer Poland in five weeks?

Poland fell in five weeks because it was attacked from two sides at once, under a deal its attackers had already signed. In late August 1939, Nazi Germany and the Soviet Union signed a non-aggression pact in Moscow. A secret protocol split Poland between them. In the West, the protocol's existence was only proven at the Nuremberg trials, after the war.

Germany still wanted an excuse. On the night of 31 August, German units dressed as Polish soldiers staged a fake attack on a radio station at Gleiwitz. Hitler had already ordered the invasion for 4:45 the next morning. Poland had mobilized only about 70 percent of its planned forces. That cut its army's fighting strength by roughly a third before the first shot.

Britain and France declared war on Germany on 3 September, but their help stayed very limited. Then, on 17 September, the Red Army invaded from the east, as the secret protocol foresaw. Poland's defence plan collapsed, and its government ordered its troops to evacuate to neutral Romania. By 6 October, Germany and the Soviet Union controlled the whole country. Poland never formally surrendered.

One famous image from the campaign is a myth: Polish cavalry never charged German tanks with lances and swords. At Tuchola Forest, a cavalry regiment attacked German infantry to cover a Polish retreat. Armored cars then caught the riders in the open. Reporters who saw dead horses lying near the vehicles told a story of sabres against tanks, and German propaganda spread it. The real hidden story is quieter. Polish codebreakers had been reading Enigma messages since 1932. Five weeks before the war, they handed their methods to Britain and France.