Guiseppe Bardari’s Italian libretto for Gaetano Donizetti’s opera Maria Stuarda, based on Friedrich von Schiller’s German play Maria Stuart, expands Schiller’s fictional invention of a competition between Elizabeth Tudor and Mary Stuart for the love of the Earl of Leicester , and makes an explicit love triangle the core of the plot. Translators of the opera into English face a semiotic clash arising from two choices made by the opera’s creators. Bardari’s libretto largely takes the catholic view that Mary was a religious heroine and Elizabeth the murderer. The Protestant view is that Elizabeth was a great ruler and Mary a potential usurper. Also, despite the opera’s Elizabethan setting, Donizetti’s music continually signifies 19th century Italy. This article discusses the problems for a performable English translation stemming from the resultant semiotic clash, only some of which were solvable by the authors in their translation for Ricordi in Milan.