Walter Giffard I was lord of Longueville in Caux, whom Jumieges tells us was the son of Osberne de Bolbec and Wevie, a sister of Gonnor, the wife of Richard I, duke of Normandy, but as the duchess Gonnor was the great-grandmother of the Conqueror, this seems impossible; consequently it is necessary to be contented with the conclusion that he was descended from this union. In 1035 with Hugh de Gournay he joined in the attempt of Edward, son of king Ethelred, to recover the crown of England, and in 1053 he was left by duke William in command of the forces blockading the castle of Arques, at which time he was lord of Longueville and already past the prime of life. He was, in 1054, one of the four commanders entrusted with the defence of Caux, in which Longueville was situated, which developed into the battle of Mortimer. Walter later made a pilgrimage to St-Iago de Compostella, Spain, where he received the gift of a horse from the king, who had a great friendship for him. This horse Walter presented to duke William and was the first one he used in the battle of Hastings, to which engagement Walter, then an old man with "white and bald head," accompanied him. His brothers, Berenger and Osborne, also followed the duke to England. Walter contributed thirty vessels and a hundred men to the fleet, according to Taylor's list. Benoit de St-More affirms that he was struck down during the engagement and rescued by duke William himself. His reward for participation in the conquest was the earldom of Buckingham, which he received in 1070, together with large possessions, and he appears to have founded the priory of St-Michel de Bolbec in 1079. He married Ermengarde, daughter of Gerrard Flaitel, by whom he had a son, Walter, who succeeded him in the earldom. Another son (William) was chancellor to William Rufus and made bishop of Winchester by Henry I. A daughter, Rohesia, married Richard de Bienfaite, eldest son of Gilbert, count of Brionne, from which union sprung the great house of Clare. His death occurred about 1084.
--(This name appears on the Falaise Roll)