• Germany had lost land to Poland under the Treaty of Versailles.
• Many German-speaking people lived in areas that were now part of Poland.
• Germany viewed Poles as subhuman and wanted their land for lebensraum.
• The Nazi-Soviet Pact ensured Russia would not stop Germany’s invasion of Poland.
• Hitler thought Britain and France would not keep their promise to defend Poland.
• On 1 September 1939 Hitler ordered the German army to invaded Poland.
• Britain and France declared war leading to the start of the Second World War.
At 4.45 am on 1 September 1939 the German battleship Schleswig-Holstein opened fire on the Polish garrison of the Westerplatte Fort, Danzig (modern-day Gdansk), in what was to become the first military engagement of World War Two. Simultaneously, 62 German divisions supported by 1,300 aircraft commenced the invasion of Poland.
The decision of Adolf Hitler to invade Poland was a gamble. The Wehrmacht (the German Army) was not yet at full strength and the German economy was still locked into peacetime production. As such, the invasion alarmed Hitler 's generals and raised opposition to his command - and leaks of his war plans to Britain and France.
Hitler 's generals urged caution and asked for more time to complete the defences of the 'West Wall ', in order to stem any British and French counter-offensive in the west while the bulk of the Wehrmacht was engaged in the east. Their leader dismissed their concerns, however, and demanded instead their total loyalty.
Hitler was confident that the invasion of Poland would result in a short, victorious war for two important reasons. First, he was convinced that the deployment of the world 's first armoured corps would swiftly defeat the Polish armed forces in a blitzkrieg offensive. Secondly, he judged the British and French prime-ministers, Neville Chamberlain and Edouard Daladier, to be weak, indecisive leaders who would opt for a peace settlement