Maometto II (Maometto secondo) is an 1820 opera in two acts by Gioachino Rossini to an Italian libretto by Cesare della Valle. Set in the 1470s during a time of war between the Turks and Venetians, the work was commissioned by the Teatro di San Carlo in Naples. Della Valle based his libretto on his earlier play Anna Erizo. The name of the title character, Maometto II, refers to the real-life Ottoman Turkish Sultan, the Great Conqueror of Istanbul Mehmed II, who lived from 1432 to 1481.
Regarded "in some ways (as his) most ambitious opera" and as "the best of Rossini's Neopolitan operas", Maometto II failed to find an audience in Naples and, "to help ensure (its) success in Venice and Paris, he smoothed out the most audacious elements of the score". Venice first saw it on 22 December 1822 and then, translated into French and changed significantly, it was presented as Le siège de Corinthe in 1826.
Until the preparation of the critical edition of Maometto II, the composer's original intentions have remained obscure. The introduction to an early version of a critical edition (now supplanted by a new one) notes some of difficulties of determining Rossini's intentions:
- " Extraordinary for its dramatic power and the nobility of its musical content, Maometto II is also an opera that poses many textual problems, since Rossini's successive revisions were made directly in the autograph score. Using copies of the score dating back to the original productions of each of these versions, the critical edition reconstructs the text of the first version (Naples, 1820), which reflects the composer's original intentions."