Belisario (Belisarius) is a tragedia lirica 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 Naples in 1826. The plot is loosely based on the life of the famous general Belisarius of the 6th century Byzantine Empire.

Domenico Gaetano Maria Donizetti was an Italian composer, best known for his almost 70 operas. Along with Gioachino Rossini and Vincenzo Bellini, he was a leading composer of the bel canto opera style during the first half of the nineteenth century and a probable influence on other composers such as Giuseppe Verdi. Donizetti was born in Bergamo in Lombardy. At an early age he was taken up by Simon Mayr who enrolled him with a full scholarship in a school which he had set up. There he received detailed musical training. Mayr was instrumental in obtaining a place for Donizetti at the Bologna Academy, where, at the age of 19, he wrote his first one-act opera, the comedy Il Pigmalione, which may never have been performed during his lifetime.