Paolo Belzoni, author of the novel Belisarius: The First Shall Be Last, reviewed here, told me that one of the secondary sources he used was
The Life of Belisarius by Lord Mahon
Lord Mahon (wiki, handle with care), Fifth Earl of Stanhope, 1805–1875, member of parliament, was a trustee of the British Museum, proposed the foundation of a National Portrait Gallery, and facilitated the Historical Manuscripts Commission. From 1846 on he was president of the Society of Antiquaries.
He published the Belisarius biography in 1829, at the age of 25, and it was reissued in 1848, but with hardly any changes.
The work has been reprinted this year with an excellent introduction by Jon Coulston, who corrects the relative few errors in the work. The Life of Belisarius was the only excursion into ancient history by Lord Mahon, all his other writings are on modern history.
Lord Mahon writes: “It is the purpose
of my narrative to show how the genius of one man averted these
dangers, and corrected these defects; how the tottering empire was
upheld; how the successors of Augustus were enabled, for a time, to
assume their former ascendancy, and to wrest from the hands of the
Barbarians their most important possessions … His
character may not unaptly be compared to that of Marlborough, whom he
equalled in talents and closely resembled in his faults of uxoriousness
and love of money.”
The biography is meticulously researched, using all ancient sources that were available to the author; and it reads surprisingly well considering that it was written some 175 years ago.
The above 1874 sketch of Lord Mahon inVanity Fair is by Carlo Pellegrini.
Gaetano Donizetti wrote the opera Belisario, first performed on February 4, 1836 at the Teatro La Fenice, Venice. From the synopsis of Act III: [Meanwhile] the blind Belisarius has led the Byzantine army and defeated the Alann, who had threatened Byzantium, but an arrow has mortally wounded him. He is carried in dying, and the sorrowing emperor promises to be a father to Alamir and Irene.
For JSTOR subscribers, there is Donizetti's ‘Belisario’ by Andrew Porter, The Musical Times, Vol. 113, No. 1549 (Mar., 1972), pp. 257-259+261.
I did find three CDs:
Belisario (Gianandrea Gavazzeni, Alberto Carusi, Augusto Veronese, and Bruno Sebastian)
Belisario (Gianandrea Gavazzeni, La Fenice Theater Orchestra, Bruno Sebastian, and Giuseppe Taddei)
Belisario (Gianfranco Masini, Colon Theater Orchestra, Buenos Aires; Mara Zampieri, and Renato Bruson)
Belisarius at Wikipedia (with the usual caveat)