After World War One, Allied countries decided that Germany was the main country to blame. The treaty said that Alsace-Lorraine had to be returned to France, Germany was forbidden to unite with Austria, the Army was restricted to only 100,000 men , pay about $72 billion in reparations e.t.c . These terms weakened Germany and made its people angry, which meant that they would turn to anyone as a leader, even Adolf Hitler. (LONG TERM)