In 857 Montorio was already part of the possessions of the Abbey of Farfa, as it appears from the chronicles written by the Cistercian monks. In the eleventh century, the inhabitants took shelter around a castle on a hill to escape the Barbarian invasions, where the medieval village was formed.
In a 1339 in a bull of Benedict XII it is still among the property of the Abbey. The village was administered from the Abbey until the second half of the fourteenth century when it was purchased by the Savelli together with Poggio Moiano. The Savelli had possession until 1462.
When Pope Pius II (1458 – 1464) confiscated it and sold it to the Cesarini. Only in 1569, and for a brief period, did the Savelli returned again to administer it. In 1577, it subsequently passed to the Orsini and then to the Barberini in 1644.