The parish church of Val d'Elsa already existed and had an archpriest in the 11th century. In 1061, Pope Alexander II ordered the creation of a Chapter of Canons. Pope Paschal II, in 1112, joined the parish of S. Giovanni, Faustina and Giulitta with the parish of S. Salvatore in Colle under one and the same archpriest. They were directly subject to the pope. That status was contested regularly by the bishops of Volterra, however, and they finally obtained a favorable ruling from Pope Clement III on 24 January 1188. The archpriests, though, continued the litigation, until Pope Clement VIII settled the matter in 1592. The Collegiate Church nullius dioecesis of Ss. Giovanni, Faustina e Giulita in Val d'Elsa was apparently established by Pope Urban VI in 1386, from territory removed from the Diocese of Volterra. The diocese of Colle was established by Pope Clement VIII on 9 June 1592, in the bull "Cum super universas". The territory of Colle was created a city. The impulse for the new diocese came from Ferdinando I de' Medici, Grand Duke of Tuscany, as the papal bull and a letter from Ferdinando to the people of Colle indicate. The new bishop, Usimbardo Usimbardi, a Canon of the cathedral of Florence and a personal friend of Duke Ferdinando, was appointed on the same day as the establishment of the diocese. The Chapter, which staffed and administered the new cathedral, was composed of three dignities and twelve Canons. Bishop Usimbardo Usimbardi held the first diocesan synod in April 1594, and promulgated a set of Constitutions for the government of the diocese.
Reorganization of dioceses
In a decree of the Second Vatican Council, it was recommended that dioceses be reorganized to take into account modern developments. A project begun on orders from Pope John XXIII, and continued under his successors, was intended to reduce the number of dioceses in Italy and to rationalize their borders in terms of modern population changes and shortages of clergy. The change was made urgent because of changes made to the Concordat between the Italian State and the Holy See on 18 February 1984, and embodied in a law of 3 June 1985. The change was approved by Pope John Paul II in an audience of 27 September 1986, and by a decree of the Sacred Congregation of Bishops of the Papal Curia on 30 September 1986. The diocese of Colle di Val d’Elsa was united to the dioceses of Siena and of Montalcino. Its name was to be Archidioecesis Senensis-Collensis-Ilcinensis. The seat of the diocese was to be in Siena. The former cathedral in Colle and the former cathedral in Montalcino were to have the honorary title of co-cathedral, and their chapters were to be the Capitulum Concathedralis. There was to be only one episcopal curia, one seminary, one ecclesiastical tribunal; and all the clergy were to be incardinated in the Archdiocese of Siena-Colle di Val d'Elsa-Montalcino..
Bishops of Colle di Val d'Elsa
Erected: 5 June 1592 Latin Name: Collensis Metropolitan: Archdiocese of Florence