In June, 1843, Verdi signed a contract with the Teatro La Fenice, Venice, for a new opera; it would be his fifth work for the stage and his first for a theater other than Milan's La Scala. Verdi persuaded the young poet Francesco Maria Piave to write a libretto based on Victor Hugo's play, Hernani, of 1830. Ernani would be the first of Verdi and Piave's many collaborations, and was very popular from its first performance on March 9, 1844. Ernani represents a turning point in Verdi's career. Because his previous operas had been composed for La Scala, he had grown accustomed to writing works for a large stage appropriate for immense choral scenes. For the significantly smaller La Fenice, Verdi had to develop a more intimate drama focusing on personal conflict and confrontation. To do this, he had to compose in a different way, leading him to alter the traditional set "numbers" of Italian opera.
One of Verdi's innovative strokes happens early in Ernani. In the first scene of Act One, Ernani describes his love for Elvira, whom he wants to steal from Don de Silva, her fiancé. The cavatina is organized in the traditional double-aria format, but Verdi extends the first half, "Come rugiada al cespite," distorting its proportions in order to convey Ernani's obsession with Silva. Elvira's cavatina in the next scene is similarly expanded. The later duet between Elvira and Don Carlos is one of the first examples of what would become a common formula for Verdi's duets: the first half is recitative-like in its quick text declamation, with melodic continuity provided by the orchestra. In the second part the characters have contrasting melodies -- Carlos' lyrical and Elvira's aggressive -- representing their dissimilar feelings. Most impressive is the "Recitative e Terzo" in the middle of Act Two. A disguised Ernani confronts Elvira and Silva; the resulting trio is primarily a combination of solos by Ernani and a duet for Elvira and Ernani. Later in the act, when Ernani makes his foolish, deadly deal with Silva, brass instruments intone a passage that first appeared in the overture and will sound again, at the close of the drama. The high point of the third act is Carlos' aria, "O de' verd'anni miei," in which he, waiting to learn if he has been elected Holy Roman Emperor, tells himself he must change and become an upright person. As the aria progresses, the florid style of Carlos' previous music gives way to broader, more confident expression. Verdi comes full circle in the finale of Act Four, in which Ernani must commit suicide in accordance with his pact with Silva. As Silva reminds him of the deal, the solemn brass chords return to prod Ernani toward his death.