Answer.
After the end of the first world war Germany and the allied powers signed the Treaty of Versailles. The treaty required "Germany [to] accept the responsibility of Germany and her allies for causing all the loss and damage" and to disarm their army. The cost for the loss and damage during the war was estimated to about US$442 billion, which Germany had to pay. The treaty of Versailles basically sucked for Germany and caused a great depression. When things go bad people generally want someone to blame and Hitler offered this. He blamed the treaty on the government and that Germanys army had not really lost the war. He also promised that they would take back what was theirs and recover territory and pride lost because of the treaty. All this made people who though the treaty was humiliating like him and vote for him.