The Legend of the Vengeance for Bevis is found only in Andrea da Barberino’s I Reali di Francia, of which it forms the Fifth Book. The original Italian can be found here. There is no English translation.
Two years after Buovo’s death, King Sinibaldo of Armenia meets his brothers Guido, Sinibaldo, and King Guglielmo of England in London, with many knights, including Sinibaldo’s son Guerrino and Guido’s son Bernardo of Clairmont. They swear vengeance. Since Galione, who killed Buovo, is living in Babylon, richly honored by the Sultan, they decide to kill his six sons instead. Galione’s wife learns of their wicked plan, however, and flees with her children to King Pepin. Pepin throws them all in jail and confiscates their lands. He will not let Buovo’s sons kill them, but gives them 15,000 knights and the Oriflamme to fight against Galione and the Sultan. Also joining the Christians is King Sicurans of Hungary. They lay siege to Damietta, Galione comes to relieve it, but they capture him and cut him to pieces. Sinibaldo leaves Armenia in the hands of a viceroy, since Pepin gives him Burgundy, Mayence, Savoy, and Provence. Pepin pardons the sons of Galione and gives them Flanders, and persuades Sinibaldo to restore to them Maganza, Losanne, and Poitiers. Sinibaldo founds the city of Mongrana in Champagne, and from that castle the House of Mongrane took their name.
In the version of Bovo d’Antona in octaves, printed in 1480, as has been said, Bovo is killed by Richier of Maganza’s vassal Gualtier. The citizens seize him and imprison him, and Bovo’s sons Sinibaldo, Guidone, and Tedrise besiege and sack Maganza.
Let thus much suffice for the Legend of the Vengeance for Bevis of Hampton.