CARPENTRAS, DIOCESE OF. - A town and ancient diocese in the department of Vaucluse, deriving its name from the Celtic Carpentorate. The first bishop of whom we have record is CONSTANTIUS, who was represented at the Council of Riez (439) and was present at those of Orange (441) and Vaison (442). Later we find a JULIAN (517-29), and then SIFREDO (Siffreini), who was buried in the basilica of the Most Holy Trinity at Venasque. In the 6th century this basilica seems to have been united to Carpentras, since CLEMATIUS, Sifredo’s successor, signed the Council of Orléans (541) as bishop of the cities of Carpentorate and Vindasum.
However, up to the mid-13th century the list of bishops of Carpentras contains many gaps. In 1228, by the Treaty of Paris, Carpentras—which belonged to the county of Venasque (whence the Comtat Venaissin)—passed into the possession of the Holy See and became the ordinary residence of the papal legates. In 1475 the diocese, which until then had been under the ecclesiastical province of Arles, was placed under the jurisdiction of the new diocese of Avignon. From the 16th century many of its bishops were Italians; the diocese was small in extent and in 1709 comprised 29 parishes. Suppressed in 1802, it was definitively reunited to Avignon in 1818.