Tristan und Isolde (Tristan and Isolde, or Tristan and Isolda, or Tristran and Ysolt), WWV 90, is a music drama in three acts composed and written by Richard Wagner between 1857 and 1859, and largely based on the romance by Gottfried von Straßburg. It was premiered in Munich in 1865. Wagner's composition of Tristan und Isolde was inspired by his affair with Mathilde Wesendonck and the philosophy of Arthur Schopenhauer. Nowadays Tristan and Isolde is considered one of the most important pieces of operatic repertoire, notable for its advances in the use of chromaticism, tonality, colour, and other harmonic devices. The very first chord in the piece, called the 'Tristan Chord', was a great symbolic significance in the movement away from tonal harmony, as it consists of a dissonant chord that resolves into another dissonant chord.
