The Archdiocese of Ancona–Osimo () is a joint ecclesiastical territory and metropolitan see of the Catholic Church in the Marche region of Italy. It has existed in its present form since 1986, when the Archdiocese of Ancona was united with the historical Diocese of Osimo. Since earliest times, the diocese has been directly subject to the Holy See without intermediate authorities. The archbishop has his episcopal throne in the Cathedral of Ancona, while the Cathedral of Osimo has the status of a co-cathedral. In the 17th, 18th, and 19th centuries, the archbishop of Ancona was frequently a cardinal. One, Prospero Lambertini, became Pope Benedict XIV. History On 19 October 1422, by virtue of the bull Ex supernae majestatis, Pope Martin V decreed the union of the diocese of Ancona and the diocese of Numana (Humana, Umana). Except for the title, the diocese of Numana was completely suppressed. On 14 September 1904, the Consistorial Congregation of the Papal Curia issued a decree, which had been approved by Pope Pius X, elevating the diocese of Ancona-Numantia to the rank of archiepiscopal see, without any suffragans and with the status and geographical definition of the diocese unchanged. The decree also granted the archbishops the use of the pallium and the archiepiscopal cross, but only within the confines of their own diocese. Cardinal Achille Manara was continued as head of the archdiocese, now as archbishop. On 15 August 1972, by the bull Qui apostolico officio, Pope Paul VI created the new ecclesiastical province of Ancona, and granted its archbishop the status of Metropolitan. The ecclesiastical province was assigned the suffragan dioceses of Jesi (Aesina) and Osimo (Auximana). On 5 July 1975, having obtained the permission of Pope Paul VI, the Congregation of Bishops ordered that the title of the archdiocese should only be the Archdiocese of Ancona. The title of Numana was reserved, to become a titular bishopric. The diocese of Ancona was united to the diocese of Osimo by a decree of the Congregation of Bishops on 30 September 1986. Its name was to be Archidioecesis Anconitana-Auximana. The seat of the diocese was to be in Ancona. The former cathedral in Osimo was to have the honorary title of co-cathedral, and its chapter was 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 diocese