``Das Judenthum in der Musik'' (German, ``Jewishness in Music'', but normally translated: Judaism in Music), (in German spelled after its first publication ``Judentum'') is an essay by Richard Wagner, attacking Jews in general and the composers Giacomo Meyerbeer and Felix Mendelssohn in particular, which was published under a pseudonym in the ``Neue Zeitschrift für Musik'' (NZM) of Leipzig in September 1850. It was reissued in a greatly expanded version under Wagner’s name in 1869. It is regarded by many as an important landmark in the history of German antisemitism.