 As an agent of the emperor, Benedetto acted as an ambassador to Peter III of Aragon in 1280–1282, and took part in the negotiations that led to the Byzantine–Aragonese alliance and the outbreak of the War of the Sicilian Vespers that ended the threat of an invasion of Byzantium by Charles I of Anjou.Benedetto returned to Genoa in 1284 and was made an admiral.He was the principal commander of the Genoese fleet which defeated Pisa at the Battle of Meloria.