The little fortress had been incorporated into the Papal States from their historic beginnings with the Lombard king Liutprand's Donation of Sutri (728) to Pope Gregory II, but the lords of Viterbo held it from 1110 to 1134. By 1145, Pope Eugene III was installed at Vetralla, safely removed from the violence and party strife of Rome; from here he issued his bull Quantum praedecessores, calling for the Second Crusade.