The diocese of Cagli e Pergola was a Roman Catholic ecclesiastical territory in the Marche, central Italy, in the province of Pesaro and Urbino. Up until 1563 it was under the direct supervision of the Roman pontiff. In that year, the diocese of Urbino was elevated to metropolitan status, and Cagli became a suffragan see of Urbino. The diocese was abolished as an independent entity in 1986, when it was incorporated into the diocese of Fano-Fossombrone-Cagli-Pergola. It was still a suffragan of the archdiocese of Urbino.
The historical diocese of Cagli was renamed in 1819.Pergola, which had been in the diocese of Urbino, was raised to the rank of an episcopal city and united to the See of Cagli.
Bishop Egidio (1243–59) had many controversies with the municipality of Gubbio. Under his successor the Ghibellines revolted against the papal power. After the death of Bishop Jacopo (1276), the Ghibelline canons wished to elect a noble, Berardo Berardi, while the Guelphs elected Rinaldo Sicardi, Abbot of San Pietro di Massa. As a result the see remained vacant for some years. Finally Berardo was made bishop of Osimo, and Sicardi died, whereupon a certain Guglielmo was elected bishop (1285). Civil discords, however, did not cease, and after a terrible massacre, Cagli was burned by its own citizens.
It was afterwards rebuilt on the plain of St. Angelo, and Pope Nicholas IV named it St. Angelo of the Pope (S. Angelo papale). Later on, however, the original name of Cagli was substituted.
In 1297 the first stone of the cathedral was laid by the Bishop Lituardo Cervati, and in 1398 Niccolò Marciari brought the building to completion. In 1503 the partisans of Cesare Borgia killed the Franciscan bishop Gasparo Golfi. His successor, a Spanish Dominican, Ludovico di Lagoria, was nearly killed by the people.
Erected: 4th Century
Latin Name: Calliensis
Metropolitan: Archdiocese of Urbino (from 1563)