Campagnano di Roma borders the following municipalities: Anguillara Sabazia, Formello, Magliano Romano, Mazzano Romano, Nepi, Rome, Sacrofano, Trevignano Romano.
In 419, Eulalius, competitor of Pope Boniface I, was made Bishop of Nepi; Bishop Paulus was sent as visitor to Naples by Gregory the Great; Bishop Stephanus, in 868, was one of the presidents and papal legates of the Council of Constantinople against Photius.
In 738 the Lombard duke Transamund of Spoleto captured the Castle of Gallese, which protected the road to Perugia to the north of Nepi.
In the spring of 1456 he was named Captain-General of the Church and castellan of Sant'Angelo, in the autumn of the same year Pope made him Governor of Terni, Narni, Todi, Rieti, Orvieto, Spoleto, Foligno, Nocera, Assisi, Amelia, Civita Castellana, and Nepi, and at the beginning of 1457 the governorships of the provinces of Patrimony and Tuscany were added to these.
Pier Luigi and his son, Ottavio, declared they would have pay 9,000 golden ducati every year to the Holy See, and, in exchange, they gave back the Duchies of Camerino and Nepi.