Why Germany invaded Poland

One of the first things Hitler did when he came into power was to sign a treaty of non-aggression with Poland. So why did he invade Poland on September 1st 1939? Better yet, why sign the non-aggression pact with Poland at all?

When Hitler signed the pact with Poland many German people were unhappy about the move. Germany had suffered many losses to Poland after the First World War thanks to the Treaty of Versailles. In this treaty the German provinces of West Prussia, Poznan, and Upper Silesia have been awarded to Poland stripping Germany of many of its valuable and industrial resources. However, Hitler felt the pact was necessary in order to prevent a military alliance between France and Poland while he re-armed Germany.

The Treaty of Versailles had not just claimed German territory; it had also stripped Germany of its army, limiting it to a mere 100,000 men, establishing a demilitarized zone (DMZ) on the southern border (Rhineland) to protect neighboring countries and more. Hitler intended to bring power back to Germany and to do this he needed to buy some time while he built up the German army effectively breaking the Treaty of Versailles.

Hitler began rebuilding the German army and re-militarized the DMZ, but Britain and France were reluctant to start another war so began the process of Appeasement. In this they allowed the re-militarization and signed away Czech borders to Germany in order to try to satisfy Germany’s needs. Germany took this opportunity to dissolve the Czechoslovakian state completely in violation of the Munich Agreement.

Britain and France were still desperate not to start a war and responded to the issue by guaranteeing the integrity of Poland. Germany was still satiated and since so far it had received no resistance to its hostile actions Hitler decided the time was right to take Poland. In order to obtain this, Hitler first made a pact of non-aggression with Russia despite the fact that they were sworn enemies. In this pact they agreed to split Poland between them thus enabling Hitler to move on with the invasion of Poland.


Poland was not just invaded for mere revenge. Despite the fact that many Germans felt hostile towards Poland and resentful that they were granted various German assets after the First World War, one of the key reasons why Poland was invaded was actually because of the Polish Corridor. The Polish Corridor was a name given to the fact that Poland, while mostly central, had a “corridor” of land that lead to the sea which essentially cut straight through Germany. Germany was cut off from East Prussia and relatives left stranded on either side while in the meantime Poland enjoyed its new connection to the sea alongside the trade and resources it provided. Hitler determined to reclaim this corridor and re-unite Germany as whole once again as well as rebuilding its navy and import trades.

Germany invaded Poland on 1st September 1939 and just three weeks later on September 28th 1939 Poland surrendered entirely. This time, Britain and France could no longer ignore Germany’s actions and declared war on Germany on September 3rd 1939.