It's hard to believe that they just convinced an entire nation that the Jews were to blame without any supporting arguments or some basis in fact. How did the Nazis justify this argument?
http://www.reddit.com/r/AskHistorians/comments/2s1g5g/ive_read_that_hitler_blamed_jews_largely_for/
Two related answers I've given on the subject.
Essentially, the economic hard times of both the early 20's and early 30's were blamed (falsely) on the reparations of the Treaty of Versailles, which was in turn the result of German defeat in WWI. German defeat in WWI in 1918 was in turn blamed on the socialists/communists/Marxists in general, and on the Jews; in the European far right, the former and the latter were seen as virtually one and the same.