[2] On the other hand, when in the fifth and sixth centuries bands of Christian Britons emigrated from Great Britain to Armorica and formed on its northern coast the small Kingdom of Domnonée, the Gospel was preached for the first time in the future Diocese of Dol and Diocese of Aleth.

Among these missionaries were St. Armel, who, according to the legend, founded in the sixth century the town of Ploermel in the Diocese of Vannes and then retired into the forests of Chateaugiron and Janzé and attacked Druidism on the very site of the Dolmen of the Fairy Rocks (La Roche aux Fées); St. Méen (Mevennus) who retired to the solitudes around Pontrecoët and founded the monastery of Gael (550), known afterwards as St. Méen's; and St. Samson and St. Malo.

[4] Louis Duchesne is of opinion that the St. Amandus reckoned by some scholars[5] among the bishops of Rennes at the end of the fifth century is the same as St. Amand of Rodez.

[6] In 1180 Bishop Philippe, acting in accordance with a dream (it is said), began the replacement of the old cathedral with a new edifice; the eastern part of the building was erected, but various delays hampered the completion of the whole structure.

[10] The royal pouillé of 1648 names six dignities, omitting the Succentor and adding the Theologian and Penitentiary.

[13] In accordance with the terms of the Concordat of Bologna of 1516, between King Francis I of France and Pope Leo X all bishops in France (which at the time did not include "the Three Bishoprics", Metz, Toul and Verdun) were to be nominated by the King and approved (preconized) by the Pope.

The practice did not apply during the French Revolution, when the Civil Constitution of the Clergy mandated the election of bishops by qualified electors in each of the new départements of the republic.

[16] During the French Revolution Claude Le Coz (1760–1815), Principal of the Collège de Quimper, was elected Constitutional Bishop of Ille-et-Vilaine.