Answer:
Harsh treatment towards Germany and that Hitler felt like the allies caused everything wrong with Germany.
Step-by-step explanation:
At the end of WWI, the treaty of Versailles took Gemany's land, stripped their military, and hit them hard financially. they started printing out so much money that their currency was useless. the U.S. let them borrow 40 mil dollars but when the market crashed, they wanted their money back. One man in Germany thought that all of this was the allies fault and he thought he could fix everything. His name was Adolf Hitler. He promised he would fix everything and then him and the Nazi party rose to power and went to war with all of the european powers with the U.S. joining in shortly after. In conclusion, WWII.