Conan I of Rennes

Conan assumed the title of Duke of Brittany in the spring of 990 following his attack on Nantes and the subsequent death of Count Alan.

Conan I had to ally himself with Odo I, Count of Blois in order to defeat Judicael Berengar before he could assume the title of Duke.

[3] In a charter dated 28 July 990, Conan gave the lands of Villamée, Lillele and Passille to Mont Saint-Michel, all of which later became part of the seigneury of Fougères.

"[3] Richard I had married the daughter of Hugh I the Great, and after this marriage had re-asserted his father's claim as Overlord of the Breton duchy.

[3] Conan I's pact with Normandy strengthened that assertion but the historical documentation for that Overlordship claim remains doubtful because it largely appears only in the less than authoritative writings of Dudo of Saint-Quentin.