One of the least savory of the offshoots of Theosophy; perhaps it will be enough for me to say that Theosophy became very popular in the 1920s, not least in Germany, for you to intuit why.
The esoteric doctrine of Armanism, developed by the improbably named Guido von List, of Vienna, fixed upon the Theosophical description of history as an evolution in stages, but in place of Madame Blavatsky's universal Aryan race, the proponents of Armanism put the Indo-Europeans, which they preferred to call »Ario-Germans« to accord with their theory that the Germanic tribes were the pure descendants of the Aryans whereas all other peoples were to greater or lesser degree degenerates. The Armanists combined the reïncarnation doctrines of Theosophy with the Old Norse afterlife of Valhalla, affirming that all men in time will rise to the station of Einherjar, which they understood to be the enlightened, perfect form of a man. They fixated on futhark runes; they claimed that the old, true, pagan religion was one of solar worship and that the swastika was the immemorial symbol of the sun. If this is beginning to sound horribly familiar, congratulations: you're sentient.
Although Armanism was actually outlawed by the Nazis, its ideas were soaked up wholesale by the proto-Nazi Thule Society, of which many prominent Nazis were members, and by Deutsches Ahnenerbe, the »archæological« society of the SS; while it would be a mockery to say that Nazism itself arose from Armanism, the latter did provide a great deal of Nazi mythology. Who can say what effect this had, who can rate the evil of such a thing? You must apply your own judgment, but we may safely assume that the addition of a compelling narrative to Nazi beliefs didn't have a net-positive effect on history.