Because the subject matter involved the mistress of a Neapolitan king, and may thus have caused difficulties with the Italian censors, Donizetti decided that the opera should be presented in France.

L'Ange de Nisida incorporated many of the manuscript pages from Adelaide, an unfinished score that Italian composer Gaetano Donizetti was probably working on in 1834, from a libretto of unknown origin.

Because the subject matter of L'Ange involved the mistress of a Neapolitan king, and may thus have caused difficulties with the Italian censors, Donizetti decided that the opera should be presented in France.

[2] Additionally, in September 1839, the French press had announced La Fiancée du Tyrol, a translation of Donizetti's 1833 opera Il furioso all'isola di San Domingo.

[3] In October 1839, he wrote to a friend in Naples: "La Fiancée du Tyrol will be Il furioso amplified, L'ange de Nisida will be new.

For example, The Musical Times journalist Winton Dean wrote of the Italian version of La favorite in 1979: "[I]t was expanded from an unperformed three-act French opera, L'Ange de Nisida.

[11] Joly's company had premiered the French version of Donizetti's Lucia di Lammermoor the previous year, and L'Ange was meant to be its successor.

[7] Later in January, Joly terminated all opera productions of the Théâtre de la Renaissance company due to financial hardship, despite a reported 5,000-franc loan from Donizetti.

[7] Writing for the Cambridge Opera Journal, Mark Everist referred to L'Ange as one of "the most spectacular casualties of the collapse of music drama at the Théâtre de la Renaissance".

The finished product was an amalgamation of the unfinished Adelaide, the never-performed L'Ange de Nisida, and new material worked into the score by Donizetti and into the libretto by Scribe.

[17] Ashbrook has compared the surviving autograph scores of L'Ange de Nisida and La favorite to determine precisely how much material it provided for the latter.

[20] The score was reconstructed over a period of eight years by musicologist Candida Mantica from pages discovered in the Bibliothèque nationale de France which were scattered in 18 different folders as well as archive research in both Europe and the US.

In a letter to his close friend Tommaso Persico, Donizetti expressed his desire to give the title role to Juliette Bourgeois, a temperamental soprano who requested a large sum of money to perform in France.

(She was later to create the title role in Donizetti's La fille du régiment)[2] Leone de Casaldi is an exiled soldier who makes a forbidden journey to the island of Nisida, outside Naples, Italy, to see Sylvia, with whom he is infatuated.