Fidelio Fidelio Fidelio (originally titled ; English: "Leonore, or The Triumph of Marital Love"), Op. 72, is Ludwig van Beethoven's only opera. The German libretto was originally prepared by Joseph Sonnleithner from the French of Jean-Nicolas Bouilly, with the work premiering at Vienna's Theater an der Wien on 20 November 1805. The following year, helped shorten the work from three acts to two. After further work on the libretto by Georg Friedrich Treitschke, a final version was performed at the Kärntnertortheater on 23 May 1814. By convention, both of the first two versions are referred to as "Leonore". The libretto, with
Fidelio a rival nobleman, Pizarro. In revenge, Pizarro has secretly imprisoned Florestan in the prison over which he is governor. Simultaneously, Pizarro has spread false rumors about Florestan's death. The warden of the prison, Rocco, has a daughter, Marzelline, and an assistant, Jaquino, who is in love with Marzelline. The faithful wife of Florestan, Leonore, suspects that her husband is still alive. Disguised as a boy, under the alias "Fidelio", she gains employment working for Rocco. As the boy Fidelio, she earns the favor of her employer, Rocco, and also the affections of his daughter Marzelline, much to Jaquino's chagrin. On