The Ancient Diocese of Vaison (Lat. dioecesis Vasionensis) was a Roman Catholic diocese in France, suppressed in 1801, with its territory transferred to the diocese of Avignon. It had been one of nine dioceses in the ecclesiastical province presided over by the archbishop of Arles, but a later reorganization placed Vasio under the archbishop of Avignon. Jurisdiction inside the diocese was shared between the bishop and the Comte de Provence, higher justice and the castle belonging to the Comte, and civil justice and all other rights belonging to the bishop. The cathedral was served by a chapter which had four dignities: the provost (praepositus), the archdeacon, the sacristan, and the precentor. There were also six canons, each of whom had a prebend attached to his office.