List of Breton saints

Breton saints refers to one of two groups, the innumerable people who lived, died, worked in, or came to be particularly venerated in the nine traditional dioceses of Brittany (Cornouailles, Dol, Leon, Nantes, Rennes, Saint-Brioc, Saint-Malo, Treguier, Vannes) who were accepted as saintly before the establishment of the Congregation of Rites (now the Congregation for the Causes of Saints), or those saints, blesseds, venerables, and Servants of God who have come to be recognized since that time.

Before the Bretons came, the land now known as Brittany was known as Armorica within the Roman province of Gallia Lugdunensis. The earliest saint associated with this region is Saint Anne, mother of Mary (mother of Jesus), said by tradition to have been Armorican, and she is the patroness of Brittany. She also appeared to Yves Nicolazic, to whom she spoke in Breton.

After her, the earliest saints in what is now Brittany have dates which are sometimes unclear, but tradition holds they go back to the earliest days of the Church. One Saint Maxime, said to have been the disciple of Saint Philip the Apostle, was sent to preach among the Gauls and was made the first Bishop of Rennes. He may have been accompanied by saints by the names of Clarus and Justus. Pope Saint Linus, the second Bishop of Rome, sent Saints Clair and Adeodatus; this is said to be the Saint Clair who became the first Bishop of Nantes around AD 280 and died early in the third century, though the dates make this suspect, and Saint Adeodatus preached especially in the area of Vannes. Other Armorican saints include Saint Similien, the third Bishop of Nantes in the early fourth century, and the brother-martyrs saints Donatian and Rogatian. Saint Palladius may also have had an Armorican connection.

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