Droit du seigneur
In Mozart's "The Marriage of Figaro", which premiered in 1786 with a libretto by Lorenzo Da Ponte, the comic plot revolves around the successful efforts of the young bride and groom, Figaro and Susanna, to block the efforts of the unfaithful Count Almaviva to seduce Susanna. To achieve his aim, the frustrated Count threatens to reinstitute "droit du seigneur". It was based on a play by Pierre Beaumarchais.
Marino Faliero (opera)
Marino Faliero (or "Marin Faliero") is a "tragedia lirica", or tragic opera, in three acts by Gaetano Donizetti. Giovanni Emanuele Bidéra wrote the Italian libretto, with revisions by Agostino Ruffini, after Casimir Delavigne's play. It is inspired by Lord Byron's drama "Marino Faliero" (1820) and based on the life of Marino Faliero ("c."1285-1355), the Venetian Doge.