FERENTUM. — The Etruscan Ferento, nestled between the deep ravines of the Acqua and Vezzarella streams, was a prosperous city in the time of Augustus and the birthplace of the emperor Otho and of Flavia Domitilla, mother of Titus.
The Christian cemetery of St. Eutychius, with an inscription dating to 359 (CIL, XI, 1, 1034–3056), and—if they belong to Ferento—a Christian seal and ring, cited by De Rossi as dating to the 3rd or 4th century and found in the territory of Viterbo (Bull. d'Arch. Crist., 2 [1871], pp. 35–37), are the earliest Christian evidence, since the first certain bishop, Maximus Ferentinus, appears at the Council of 487. At the Roman Synod of 649, a bishop of F. named Polymathium subscribed, and in those of 680–81 a prelate of Polymathium is recorded, corresponding to Bomarzo, subject to Byzantine rule, where, according to Duchesne, the bishop of F. would have withdrawn in the 6th or 7th century due to the Lombard invasion, retaining jurisdiction over the part of the diocese that remained Roman. Subsequently, it followed the fate of the see of Bomarzo, which in turn was united in the 11th century with that of Bagnoregio.
In 1172, F. was destroyed by the people of Viterbo, who accused the Ferentani of the heresy of Cerdon. Remaining are the theatre, a hippodrome on the hillside, and ruins of a church from the 9th–10th century dedicated to St. Boniface, bishop of F. (Greg., Dial., I, 9). In episcopal catalogues, confusion is not infrequent between F. and Ferentinum in the province of Frosinone.