Tristan und Isolde, WWV 90, is an opera in three acts by Richard Wagner to a German libretto by the composer, based largely on the 12th-century romance Tristan by Gottfried von Strassburg. It was composed between 1857 and 1859 and premiered at the Königliches Hof- und Nationaltheater in Munich on 10 June 1865 with Hans von Bülow conducting. Wagner referred to the work not as an opera, but called it "eine Handlung".
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