I think one of his grandparents was. He was raised Catholic, however, but pretty much rejected Christianity as a young adult. He hated Christians of any kind as well as Jews, but reserved an especially twisted hatred for Jewish people, blamed them for all the ills of Germany. If he had any form of religion at all as a mature adult, it was Teutonic Paganism. A lot of occult crap in Nazi circles, apparently.
I’m aware he blamed the Jews for economic downturn in Germany at that time, and wasn’t a practising Christian, certainly not a practising Catholic.
Actually, I always thought he was an Austrian, at least by birth. Very sad how someone whose bloodline connects to a certain ethnicity or religion should rise against his or her own people and commit vile atrocities. Always thought there must have been other reasons.