Translations: engl. (H. und F. Comer), french (A. Ernst/P. Brück)
Place: Tristan’s ship, King Mark’s castle in Cornwall, Tristan’s castle

Characters: Tristan (tenor) - King Mark (bass) - Isolde (soprano) - Kurwenal (baritone) - Melot (tenor) - Brangäne (mezzo-soprano) - Shephard (tenor) - Mate (baritone) - Voice of a young sailor (tenor)

In 1856 pressing financial obligations forced Wagner to interrupt the composition of the "Ring” to work on "Tristan und Isolde". He initially planned a work that was modest in its production and performance demands. The project was also given priority not least because of the prospect of the royalties which he would then receive. He once again turned to Breitkopf & Härtel for the performance material: "‘Tristan und Isolde’ is scheduled to be given its first performance at the end of this year. I still hope that it will take place in Karlsruhe under my guidance. Due to the celebrity that I have now acquired, I assume that a new and easily performable work of mine should be able to spread very quickly across the German stages in its first winter season.” Wagner was wrong. although the publisher had spent a great deal of time and money in producing preliminary material, Wagner wrote to Breitkopf & Härtel from Munich in November 1864: "The squalor of Germany’s opera singers and the vile condition of its opera houses have so far dissuaded me from allowing a performance of ‘Tristan und Isolde’. What I needed was an impassioned young monarch to restore my courage. Next spring you will hear about the work’s premiere in Munich, and you will then hopefully become more confident about this publication.”