It is said that during the siege by the Greeks, the young Romoaldo, finding himself in serious trouble, asked his servant to reach his father in Pavia, where he was engaged in “war actions”, to ask him to send reinforcements. The soldier managed to reach the Duke and returned towards Benevento to inform his Prince of the imminent arrival of help. But before reaching his destination he was captured by the men of Constans II and in exchange for his freedom he agreed to lie to his Prince; however, when he was before his Lord, Cavalier Gesualdo openly announced that the Duke father had already ordered his soldiers to reach Benevento. Constans II, forced to lift the siege of the city, did not spare Cavalier Gesualdo and had him captured and beheaded.
Gesualdo repeatedly proved his attachment to the Dukes, and this earned him various trusted positions, including the construction of a large fortification to defend the wide possessions of the Lords. A point in a very strategic position was chosen, on the northern bank of the Fredane river, in whose valley one of the main roads leading to Benevento wound, on a hill 650 meters high, from where a vast portion of the territory of the Gastaldato of Quintodecimo could be controlled; there a manor was built, and over time many houses began to rise nearby, thus giving rise to a true village. Duke Grimoaldo thought of granting that portion of the duchy as a fief to his faithful Knight and his descendants, and the village took its current name from them. Gesualdo also became the lordship of nearby towns such as Frigento, Mirabella Eclano, San Mango. In the 12th century the fortification became a real Castle, and also hosted the Benedictines of Montecassino who went to Lagopesole to meet Pope Innocent II. When the Lombard family of the Gesualdo died out, the Norman dynasty began in 1078. The official news of the settlement dates back to when the feudal lord of the village was William of Hauteville, lord of Lucera and nephew of Robert Guiscard; born from an adulterous relationship between Roger Borsa, Duke of Apulia, and Maria, a woman from Salerno, he had, besides the lordship of Gesualdo, other possessions in Irpinia, and obtained from King Roger the title of Baron.
