Alan I, Duke of Brittany

Alan I (French: Alain; died 907), called the Great, was the Count of Vannes and Duke of Brittany (dux Brittonium) from 876 until his death. He was probably also the only King of Brittany (rex Brittaniæ) to hold that title by a grant of the Emperor.

Alan was the second son of Count Ridoredh of Vannes. He succeeded his brother Pascweten in Vannes when the latter died, probably in the middle of 876, and contended for leadership of Brittany with Judicael of Poher. Alan represented the power bloc of southeastern Brittany while Judicael represented western Breton interests. Eventually he and Judicael made peace in order to fight the Vikings. Judicael died in the Battle of Questembert in 888 or 889, after which Alan gained sole leadership of Brittany. In 890, Alan defeated the Vikings at Saint-Lô, chasing them into a river where many drowned.

After the death of Judicael, Alan ruled all of Brittany as it had been during the time of Salomon. He ruled not only the Breton territories of Léon, Domnonée, Cornouaille, and the Vannetais, but also the Frankish counties of Rennes, Nantes, Coutances, and Avranches, as well as the western parts of Poitou (the so-called pays de Retz) and Anjou. In the east his rule extended as far as the river Vire. He was the first Breton ruler to rule this entire territory without great opposition within the west and the last to rule the whole bloc of Franco-Celtic countries. His strongest opponent was Fulk I of Anjou, who disputed control of the Nantais with him, though Alan seems to have had the upper hand in his lifetime. His power base remained in the southeast and he was powerful and wealthy in land in around Vannes and Nantes.

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