Hitler blamed Jewish people for almost all of Germany's political, economic and social problems. He used anti-Semitic ideas that had been around for a long time.

I'm not overly read on the topic, but from what I have read Hitler suspected that Jews were after world dominance. He suspected they would not hesitate to use all possible means, including capitalism. In this way, Hitler took advantage of the existing prejudice that linked the Jews to monetary power and financial gain. Not only did he claim that Jews as capitalists referring to the Jewish bankers, were trying to rule the world, but also from a communist standpoint, ie both sides. The Treaty of Versailes had placed harsh conditions on Germany, The League of Nations would become The United Nations who supported a state for Israel in Palestine. Hitler saw this as a attempt of a Jewish European empire. Hitler wanted no part in the League of Nations and wanted Germany to remain sovereign. Of course there was a belief in an Aryan race, and the belief that Jews along with any allies wanted to wipe this out. This aryan race belief was linked to the city of Atlantis, which had been an ongoing belief among many including Francis Bacon, John Dee and alike, even Madame Blavatsky spoke of it, featuring in "The 7 root races of mankind." Hitler adopted the swastika from Tibet as a symbol of good fortune.