I am not an historian, however, it's my understanding there was a deep, deep strain of anti-Semitism in Germany before Hitler ever showed up. So it wasn't just the regular volk taking unsuspecting steps toward fascism. They wanted it; even yearned for it. Not unlike racist MAGAs.

Strain, sure. But it needn't ever have grown as much and surfaced as much as it did. At the start of the 20th century, Germany was seen as one of the best places in Europe for Jews

Yep, he clearly had a solid base to build upon, just like Trump did with his current base...

Yes there was, but that was also the case for much of Europe at the time (see for instance The Dreyfus Affair). It was only in Germany that it evolved into full-fledged nazism and genocide. The reasons for this are complex.

There was anti-Semetism in many European countries & America. That's part of why so many countries turned away Jewish refugees, & why there was an international performance of guilt after the war that was used to advocate for the creation of the state of Israel.

I received “The Coming of the Third Reich” by Richard Evans. It’s not crazy long and it goes a good job linking pre-Nazi trends in German society to the pathologies of post 1933 Germany