Terni is the ancient Interamna Nahars of the Umbrians, and the cathedral, and other churches, are built on the sites of pagan temples.

After the Lombard invasion, Terni belonged to the Duchy of Spoleto, and with the latter, came into the Pontifical States.

It was at Terni that Pope Zacharias entered into the agreement with King Luitprand for the restitution of the cities of Bieda, Orte, Bomarzo, and Amelia to the Duchy of Rome.

There were other martyrs from this city, among them saints Proculus, Ephebus, Apollonius, and the holy virgin Agape.

Among its bishops were: Among its saints: Latin Name: Interamnensis Erected: 2nd Century Latin Name: Interamnensis et Narniensis United: 12 April 1907 with the Diocese of Narni Immediately Subject to the Holy See Latin Name: Interamnensis, Narniensis et Amerinus United: 13 September 1983 with the Diocese of Amelia Latin Name: Interamnensis-Narniensis-Amerinus Name Changed: 30 September 1986 This article incorporates text from a publication now in the public domain: Herbermann, Charles, ed.