him. He had also a daughter, Christina, who married William FitzGeoffrey de Mandeville, 3rd Earl of Essex. Career When Baron Walter died in 1198, Fitzwalter succeeded to his estates, being already more than of full age and married to his first wife, Gunnor. His marriage to Gunnor had brought him 30½ knight's fees, and he inherited more than 66 from his father. He also acquired two knight's fees through Gunnor's uncle Geoffry of Valognes, and about 1204 obtained livery of seisin of the lands of his own uncle, Godfrey de Luci, bishop of Winchester. Francisque Xavier Michel said that Fitzwalter came to be "one of the greatest men in England, and one of the most powerful". His lands were mainly situated in the north, so that his interests now became close to those of a faction called the "Aquilonares", whom he would later lead in the struggle against King John. In the years following 1200, Fitzwalter is recorded as a participant in several lawsuits. In 1200 Fitzwalter was surety for half the fine incurred by his brother, Simon Fitzwalter, for marrying without royal licence. In 1201 he made an agreement in the curia regis with St Albans Abbey with respect to the wood of Northaw. Another suit sprang from his claim to the custody of the Hertford Castle as of ancient right. He withdrew this suit for a time, and in August 1202 King John made Fitzwalter warden of Hertford Castle by royal letters patent, releasing him from his family's debts to Jewish moneylenders as well. Early in 1203 Fitzwalter was in attendance on the king in Normandy, in February and March at Rouen. Fitzwalter was made joint-governor of the castle of Le Vaudreuil (near the mouth of the Eure) with Saer de Quincy, later Earl of Winchester, his half-first cousin (both being grandsons of Matilda/Maud de St Liz/Senlis). After Easter King Philip II Augustus of France took the field, and despite being well fortified and supplied, the governors of Vaudreuil surrendered at the first summons. Philip shut them up in close confinement at Compiègne, where they remained until redeemed by a heavy ransom of five thousand marks. On 5 July John issued letters patent from Rouen to certify that they had surrendered the castle by his precept, witnessed by William Marshal, but in late November Fitzwalter's cousin William d'Aubigny was still engaged in selling some of Fitzwalter's lands to