Felix Mendelssohn. Know him? He wrote Elijah, among other things. Like this:

He also has the dubious honor of being singled out as proof that Jews are incapable of true music in Wagner’s antisemitic essay on the topic. Fuck Wagner!

Mendelssohn’s grandfather, Moses Mendelssohn, was a well-known Jewish philosopher who advocated for the rights of Jews in Prussia and for religious tolerance in general. An example, which I quoted in my novel:

Brothers, if you care for true piety, let us not feign agreement, where diversity is evidently the plan and purpose of Providence. None of us thinks and feels exactly like his fellow man: why do we wish to deceive each other with delusive words?

But Felix’s father Abraham converted the entire family to Christianity when Felix was a child in a home ceremony–less out of religious fervor and more out of a feeling that the days of Judaism were over and the family needed to assimilate. Felix was always proud of his Jewish heritage. (Apparently there are some who believe that he was a crypto-Jew but there is no evidence aside from him being friendly to Jews.)

The Berlin Academy didn’t allow Jews to attend, but Mendelssohn convinced them to make an exception for his friend, Lewis Lewandowski. Lewandowski was the first Jew to attend, and wrote huge swaths of Jewish liturgical music, including this piece: