Odo, Count of Penthièvre
Odo of Rennes (Medieval Breton: Eudon Pentevr, Modern Breton: Eozen Penteur, Latin: Eudo, French: Eudes/Éon de Penthièvre) (c. 999–1079), Count of Penthièvre, was the youngest of the three sons of Duke Geoffrey I of Brittany and Hawise of Normandy, daughter of Richard I of Normandy.