The singing of "Die Lorelei" by the German soldiers was a subtle dig at the anti-semitic regime of the Nazis, since the words were written by banned Jewish poet
Heinrich Heine. Many of his books, considered "un-German," were burned in the book-burning episode at Opernplatz, Berlin, Germany, on 10 May 1933. However, his works were so popular that they were still published, but "author unknown" was the listed writer. In his 1821 play "Almansor," Heine also prophetically wrote "Dort, wo man Bücher verbrennt, verbrennt man am Ende auch Menschen." ("Where they burned books, they will in the end in burn people.")
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