D Starkl in her book "The Occult in Nazi Germany" traces the beginning of the party to the Thule Society that was operating in Munich before and after WW1. Germany at the turn of the century and later had many secret occult societies and many folks were influenced by them. Often a volkish or anti-semetic front was put up to keep things looking "legit".
A good place to look for a taste of this mentality is in the work of Hermann Hesse, his "Journey to the East" is an excellent example of the tone of the times. Also, Thomas Mann's "Dr. Faustus" retells Goethe's Faust for modern Germans (this was written during WW2 I believe).
Hitler's involvement w/ the occult has been traced to his vagabond days in Vienna. His library, confiscated by the allies after the war, contained many volumes penned (and signed) by Viennese occultists. I would say therefore, that Nazism was itself an occult organization w/ the manifestation of the SS as its priesthood. The symbolism used by them is simply too strong to ignore and of course their actions speak for themselves.
While some would make lite of this subject, we dismiss it at our own peril.
A phenomenal book. Mann's understanding of the particular "pact with the devil" that destroyed Germany is very poignant. One another level, it addresses the "problem of evil" in the human condition.