Ancient Diocese of Dol

The Breton and French Catholic diocese of Dol existed from 848 to the French Revolution. It was suppressed by the Concordat of 1801. Its see was Dol Cathedral. Its scattered territory (deriving from the holdings of the Celtic monastery, and including an enclave at the mouth of the Seine) was shared mainly by the Diocese of Rennes and the Diocese of Saint-Brieuc.

The Life of St. Samson, which cannot be of earlier date than the seventh century, mentions the foundation of the monastery of Dol by St. Samson. He was doubtless already a bishop when he came from Great Britain to Armorica, and it is he perhaps who assisted at the Council of Paris between 561 and 567. But in the biography there is nothing to prove that he founded the See of Dol or that he was its first bishop.

In the twelfth century, to support its claim against the Metropolitan of Tours, the Church of Dol produced the names of a long list of archbishops: St. Samson, St. Magloire, St. Budoc, St. Génevée, St. Restoald, St. Armel, St. Jumael, St. Turian. Louis Duchesne discounted and doubted this list. He was of the opinion that the abbey of Dol may have had at its head from time to time abbots with episcopal jurisdiction, but that Dol was not the seat of a diocese.

Under Charlemagne and Louis the Pious, the Vicariate of Dol and the monastery of St. Méen were still included in the Diocese of Aleth; so that the first Bishop of Dol was Festianus (Festgen) mentioned for the first time between 851 and 857, and installed by King Nomenoë. Among the bishops of Dol are:

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