The Italian Catholic diocese of Ferentino existed until 1986, when it was united into the new diocese of Frosinone-Veroli-Ferentino.

History

In the time of Emperor Constantine Ferentino

Ferentino

Ferentino is a town and comune in Italy, in the province of Frosinone, Lazio, 65 km southeast of Rome.It is situated on a hill 400 m above sea-level, in the Monti Ernici area.-History:...

 had its own bishop; but the first known by name is Bassus, present at Roman synods, 487 and 492-493. St. Redemptus (about 570) is mentioned in the Dialogues of Gregory the Great; and he also refers to a Bishop Boniface.

Other bishops are

• Trasmondo Sognino (1150), who died in prison;
• Ubaldo (1150), legate of Pope Adrian IV
  Pope Adrian IV
  Pope Adrian IV , born Nicholas Breakspear or Breakspeare, was Pope from 1154 to 1159.Adrian IV is the only Englishman who has occupied the papal chair...
  
   to the princes of Christendom in favour of a crusade, later the consecrator of the antipope Victor IV
  Antipope Victor IV
  Antipope Victor IV may refer to:* Antipope Victor IV * Antipope Victor IV...
  
  ;
• Giacomo (1276), legate of Pope John XXI
  Pope John XXI
  Pope John XXI, , born Pedro Julião Pope John XXI, , born Pedro Julião Pope John XXI, , born Pedro Julião (Latin, Petrus Iulianus (c. 1215 – May 20, 1277), a Portuguese also called Pedro Hispano (Latin, Petrus Hispanus; English, Peter of Spain), was Pope from 1276 until his death about eight...
  
   to Emperor Michael Palaeologus;
• Landolfo Rosso (1297), who rendered service to Pope Boniface VIII
  Pope Boniface VIII
  Pope Boniface VIII , born Benedetto Gaetani, was Pope of the Catholic Church from 1294 to 1303. Today, Boniface VIII is probably best remembered for his feuds with Dante, who placed him in the Eighth circle of Hell in his Divina Commedia, among the Simonists.- Biography :Gaetani was born in 1235 in...
  
  ;
• Francesco Filippesio (1799), legate of Julius II to the Emperor Maximilian.