Zaira is a tragedia lirica, or tragic opera in two acts by Vincenzo Bellini set to a libretto by Felice Romani which was based on Voltaire's 1732 play, Zaïre. The story takes place in the time of the Crusades and the opera's plot involves the heroine, Zaira, struggling between her Christian faith and her love for Orosmane, the Muslim Sultan of Jerusalem. It was Bellini's fifth opera, following quickly after his February 1829 composition and premiere of La straniera at La Scala.