Count William I Of Brionne and Eu DE BRIENNE OF NORMANDY

William I Of Brionne and Eu was born in 0980.  William I Of Brionne and Eu's father was Duke/Duke Richard I "The FearLess" Of Normandy and his mother was Duchess Gunnora Of Normandy DE CREPON OF DENMARK.  His paternal grandparents were Duke William I Of Normandy LONGSWORD and Sprote Of Brittany DE SENLIS; his maternal grandfather was Herbastus Herfast Forester of Arques DE CREPON. He had six brothers and three sisters, named Richard II, Richard II "The Good" Of Normandy, Robert Of Rouen, Geoffrey DE EU, Mauger Of Corbeil, William, Hawise, Emma "Beauclerc" and Beatrice. He had a half-brother named Roger I.  He died at the age of 35 in 1015.

He had a biological son named Gilbert "Crispin" Of Tillieres.