Das Rheingold (; The Rhinegold), WWV 86A, is the first of the four epic music dramas that constitute Richard Wagner's cycle Der Ring des Nibelungen (English: The Ring of the Nibelung). It premiered as a single opera at the National Theatre of Munich on 22 September 1869, and received its first performance as part of the Ring cycle at the Bayreuth Festspielhaus on 13 August 1876.
Wagner wrote the Ring librettos in reverse order, so that Das Rheingold was the last of the texts to be written; it was, however, the first to be set to music. The score was completed in 1854, but Wagner was unwilling to sanction its performance until the whole cycle was complete; he worked intermittently on this music until 1874. The 1869 Munich premiere of Das Rheingold was staged, against Wagner's wishes, on the orders of King Ludwig II of Bavaria, his patron. Following its 1876 Bayreuth premiere, the Ring cycle was introduced into the worldwide repertory, with performances in all the main opera houses, in which it has remained a regular and popular fixture.