Treaty of Versailles
As Germany owed a huge amount of money to the Allies, it started to get loans by the Americans such as under the Dawes Plan. During the Great Depression in 1932, the United States wanted all its money back. Germany refused to pay and printed more and more money to pay its debts. That led to hyperinflation and the Reichsmark was worthless. Some Germans even wanted to fight another war to get rid of it.