The countries in Europe were not happy with the terms of the Treaty of Versailles. Germany was especially angry as it received the worst of it. They were forced to give up much of their armed forces and had to pay for most of the damage. This is what led to WWII. Hitler and many other Germans were angry about how Germany was treated at the end of WWI. He rallied the German people, built up the military, and started WWII, the deadliest conflict in history.