The Italian Catholic diocese of Arezzo-Cortona-Sansepolcro has existed since 1986. In that year the historic diocese of Arezzo was combined with the diocese of Cortona and the diocese of Sansepolcro, the enlarged diocese being suffragan of the archdiocese of Florence.[1]
Arezzo was the see of a diocese in Tuscany, directly dependent on the Holy See. Tradition says it was converted by Saint Romulus, afterwards Bishop of Fiesole, a disciple of St. Paul.
It became a bishopric about 304, under Saint Satyrus. Saint Donatus, his successor, is patron of Arezzo Cathedral, also dedicated to Saint Peter the Apostle. The first eight bishops have become venerated as saints.
From 1023 to 1036 the bishop was Theodaldus, who invited Guido of Arezzo to train the cathedral singers of the plainchant.
Pope Clement XII, while his nephew Cardinal Guadagni was Bishop of Arezzo, conceded to it in perpetuo archiepiscopal insignia, the pallium and double cross.
This article incorporates text from a publication now in the public domain: Herbermann, Charles, ed (1913). Catholic Encyclopedia. Robert Appleton Company.