Johann Stauss II, who wrote the operetta Die Fledermaus and The Blue Danube Waltz, was (quoting Wikipedia)

“born in St Ulrich near Vienna (now a part of Neubau), Austria, on October 25, 1825, to the composer Johann Strauss I.

“His paternal great-grandfather was a Hungarian Jew ““ a fact which the Nazis, who lionised Strauss’s music as ‘so German’, later tried to conceal.”

In fact, after Strauss died, a group of Nazis found his grave, dug it up, and threw his bones to the winds.