One of the rarer books on the subject.

... Many books have been written about Hitler and the Holocaust, many reasons suggested to account for them. It is said that Germany in the 1930's was economically and spiritually bankrupt, that Hitler and his henchmen were madmen or simple opportunists or petty bureaucrats—or some combination of the three. Perhaps. But one explanation tends to contradict another, and when all are combined, they merge into a solution so general that nothing is explained. Understandably, then, many people are still not satisfied that the grotesque events of the Third Reich have been adequately dealt with by the historians.

In all this complicated story, there is one question which cries out for an answer: How is it that the theorists have missed a vital element, even when they themselves provide important clues? That element is the occult.

Many historians have alluded to the Nazi party's origins in an occult sect, to the occult leanings of leading Nazi officials, to the mystical rites of the SS and the Hitler Youth, to the establishment of a bureau devoted exclusively to the occult during World War II. It now seems puzzling that they should not also have given as much consideration to the underlying basis for these odd phenomena as they gave to economic and social factors. That they did not is, of course, evidence of their own dismissal—quite reasonably—of a crankish pseudoscience. But this has led, inevitably, to selective blindness. In order not to be accused of giving credence to irrational beliefs, they have failed to see those beliefs in their proper historical perspective. Since early studies always influence later ones, the interpretation of Nazi origins has tended to remain pretty much the same for the past two decades.

All the same, people do seem to have a subliminal awareness that the Nazis were involved in occultism. One often comes across references such as these: ...The Nazi horror reveals how Satanic the human soul can become.
https://exploringrealhistory.blogspot.com/2020/04/part-1-nazis-and-occulthidden.html