MAINLY BECAUSE
After the First World war there was the treaty of Versailles.The treaty of Versailles,besides stripping Germany of much of it's territory,ordered the complete disarmament of it's armed forces,except for a token army of 100,000.It even had to pay an overwheeling war reparation sum of SIX BILLION AND SIX HUNDRED MILLION POUNDS. Besides of that Rhineland had to be demilitarised and occupied by allied forces.Most of German coalfields and industrial territory were likewise put under French Jurisdiction.(To weaken the industry of Germany and so prevent the outburst WW2,they thought). The enormous costs of war caused rampant inflation.Unemployment rose to over 5 million.Large parts of the population lived in fear of falling back into 19th-century poverty.-IN GERMANY Then When Adlof Hitler became a dictator of Germany Started the OUTBREAK OF THE WW2...
Many of the seeds of World War II in Europe were sown by the Treaty of Versailles that ended World War I. In its final form, the treaty placed full blame for the war on Germany and Austria-Hungary, as well as exacted harsh financial reparations and led to territorial dismemberment. For the German people, who had believed that the armistice had been agreed to based on US President Woodrow Wilson's lenient Fourteen Points, the treaty caused resentment and a deep mistrust of their new government, the Weimar Republic. The need to pay war reparations, coupled with the instability of the government, contributed to massive hyperinflation which crippled the German economy. This situation was made worse by the onset of the Great Depression.
In addition to the economic ramifications of the treaty, Germany was required to demilitarize the Rhineland and had severe limitations placed on the size of its military, including the abolishment of its air force. Territorially, Germany was stripped of its colonies and forfeited land