Walter was the son of Osbern de Bolbec, Lord of Longueville by a sister of Gunnor, Duchess of Normandy. As such he was a cousin of William the Conqueror. From the mid 1040s Walter's name appears among the loyal supporters of William the Conqueror. Walter was at the Battle of Mortemer and was among the Norman barons who surprised and defeated Counts Odo and Renaud leading the French contingent attacking Normandy from the east. In particular, he and another great vassal Robert of Eu encountered Odo's army encamped in the village of Mortemer with no sentries and the soldiers were drunk. The Normans attacked the French while they slept, most being either killed or taken prisoner. While Odo himself escaped, when King Henry I learned of the fate of his brother Odo's army he promptly withdrew his remaining forces and left Normandy. In 1054 Walter was in charge of maintaining the siege of Arques castle, against William of Talou, who had rebelled against the Conqueror. Like many other Norman and French knights during the eleventh and early twelfth centuries, Walter served as a Christian knight in Spain against the Saracens. His epithetle Barbastre was earned when he took part in the Siege of Barbastro, an undertaking sanctioned by Pope Alexander II against the Moors in 1064, one of the more famous exploits of that time. By the time of the Conquest, Walter had returned to Normandy bearing a gift of the King of Spain for Duke William, a magnificent war-horse. The same Spanish war-horse duke William called for on the morning of the Battle of Hastings. The Spanish king in question was in all probability Sancho Ramírez of Aragon who was known for making friends and recruiting knights and soldiers from Northern France. Walter was also one of the first, if not the first in England to go on pilgrimage to Santiago de Compostela, which he did after the siege of Barbastro and before returning to Normandy. In early January 1066, after Duke William received news of the crowning of Harold Godwinson as king of England, he called together a meeting, the Council of Lillebonne, that included six of his key magnates, Walter Giffard being one of them. After telling them of his plan to invade England and take the crown they all advised him they supported him fully but suggested he call a meeting of all his vassals, which William did. In the preparation stage for the Battle of Hastings, Walter was one of the Norman magnates who provided ships for William's invasion fleet. In his case, he provided thirty. Walter was one of two who, having been offered the privilege of carrying William's standard in the battle, respectfully refused. Although by this time an older warrior with white hair, he wanted both hands free to fight. As a reward for his participation, Walter was granted the feudal barony of Long Crendon, comprising 107 manors, 48 of which were in Buckinghamshire, of which the caput was at Long Crendon, Buckinghamshire. The date of his death is not recorded, but his son Walter succeeded him before 1085.Detlev Schwennicke, Europäische Stammtafeln: Stammtafeln zur Geschichte der Europäischen Staaten, Neue Folge, Band III Teilband 4 (Marburg, Germany: Verlag von J. A. Stargardt, 1989, Tafel 695
Family
Walter was married to Ermengarde, daughter of Gerard Flaitel. Walter and Ermengarde were the parents of:
