It is said that during the siege by the Greeks, the young Romuald, finding himself in serious difficulties, 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 to Benevento to inform his Prince of the imminent arrival of aid. But before reaching his destination he was captured by the men of Constantine II and in exchange for his freedom agreed to lie to his Prince; however, when he was in the presence of his Lord, the Knight Gesualdo openly announced to him that the Duke father had already ordered his soldiers to reach Benevento. Constantine II, forced to lift the siege of the city, did not spare the Knight Gesualdo and had him captured and beheaded.
Gesualdo repeatedly proved his attachment to the Dukes, and this earned him various trusted assignments, including the construction of a large fortress to defend the extensive possessions of the Lords. A spot was chosen in a very strategic position, on the northern bank of the Fredane river, in whose valley one of the main roads leading to Benevento ran, on a hill 650 meters high, from where a large 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 real village. Duke Grimoald thought of granting that portion of the duchy as a fief to his faithful Knight and his descendants, and from these the village took its current name. Gesualdo also became the lordship of neighboring towns such as Frigento Mirabella Eclano, San Mango. In the 12th century the fortress became a real Castle, and it also hosted the Benedictines of Montecassino in its rooms who went to Lagopesole to meet Pope Innocent II. Extinct the Lombard family of the Gesualdo, the Norman dynasty began in 1078. 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, in addition to the lordship of Gesualdo, other possessions in Irpinia, and obtained from King Roger the title of Baron.
