Belisario (Belisarius) is a tragedia lirica (tragic opera) in three acts by Gaetano Donizetti. Salvadore Cammarano wrote the Italian libretto after Luigi Marchionni's adaptation of Eduard von Schenk's[] play, Belisarius, first staged in Munich in 1820 and then (in Italian) in Naples in 1826. The plot is loosely based on the life of the famous general Belisarius of the 6th century Byzantine Empire.
It premiered to critical and popular success on 4 February 1836 at the Teatro La Fenice, Venice, and was given many additional performances that season, although Donizetti scholar William Ashbrook notes that there would have been more had the opera not been presented so late in the season.
However, in spite of its initial short term success and critical reaction, as represented by a review in La Gazzetta privilegiata which stated that "A new masterwork has been added to Italian music.....Belisario not only pleased and delighted, but also conquered, enflamed and ravished the full auditorium", in the long run, had "Donizetti poured music of the calibre of his Lucia di Lammermoor into the score of Belisario the shortcomings of its wayward plot and dramatic structure would matter less". By April 1836, even the composer himself recognized that the work stood below Lucia in accomplishment.
With the success of Lucia di Lammermoor in September 1835, Donizetti moved on to stagings of Maria Stuarda, the first under that name at La Scala in late 1835. He had signed the contract in July 1835 to present Belisario in Venice, for what would be the first visit to that city since 1819, but it was not until October that the subject was finally agreed upon.
There followed discussions with impresario Natale Fabbrici about employing a Venetian librettist, Pietro Beltrame. However, not only did the composer prefer to work with a librettist known to him and with whom he could work in close proximity, but he had already begun working with Cammarano who was revising - to the composer's satisfaction - an earlier version of Belisario which the librettist had submitted to the Teatro San Carlo management in 1832.