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
Boris Godunov (opera) Boris Godunov (opera) Boris Godunov (, "Borís Godunóv") is an opera by Modest Mussorgsky (1839–1881). The work was composed between 1868 and 1873 in Saint Petersburg, Russia. It is Mussorgsky's only completed opera and is considered his masterpiece. Its subjects are the Russian ruler Boris Godunov, who reigned as Tsar (1598 to 1605) during the Time of Troubles, and his nemesis, the False Dmitriy (reigned 1605 to 1606). The Russian-language libretto was written by the composer, and is based on the drama "Boris Godunov" by Aleksandr Pushkin, and, in the Revised Version of 1872, on Nikolay Karamzin's "History of the