The former French diocese of Cavaillon (Lat. dioecesis Caballicensis) existed until the French Revolution as a diocese of the Comtat Venaissin, a fief of the Church of Rome. It was a member of the ecclesiastical province headed by the Metropolitan Archbishop of Avignon. Its seat was at Cavaillon, in the south-eastern part of what is now France, in the modern department of Vaucluse.
The Cathedral was officially dedicated to the Blessed Virgin Mary (Nôtre Dame), but popularly honored Saint Veranus, the sixth-century bishop of Cavaillon. In 1202 the Cathedral had a Chapter composed of a Provost, a Precentor, and a Sacristan, to which were added the Archdeacon and 12 Canons.
After the Concordat of 1801, the territory of the diocese passed to the diocese of Avignon.
Ancient Diocese of Cavaillon Wikipedia
In January 2009 the bishopric was revived by Pope Benedict XVI as a titular see, to provide the ever-increasing number of auxiliary bishops and Vatican bureaucrats with prelatial episcopal status. Theoretically, the titular bishop of Cavaillon belongs to the ecclesiastical province of Marseille. The current incumbent since 2009 is Krzysztof Zadarko, Auxiliary Bishop of Koszalin-Kołobrzeg (Poland).