William I., king of England, called the Conqueror, bastard son of Robert III., Duke of Normandy, by Arletta, daughter of a tanner of Falaise, was born at Falaise in 1027 or 1028. News of his father's death on pilgrimage having reached Normandy in 1035, the nobles accepted him as duke. Many of them, however, rebelled against him, and were helped by his feudal superior, Henry I. of France. His guardians were faithful to him, but three of them were murdered, and his youth was passed in the midst of difficulty and danger. In 1047 the lords of the western, or Danish, part of the duchy rebelled, and William nearly fell into their hands at Valognes. King Henry came to his help, and the king and duke defeated the rebels at Val-ès-dunes. This victory established William's power in Normandy. He ruled his duchy vigorously, and won two fortresses on the frontier of Maine. In 1051 he visited his cousin, Edward the Confessor, the English king, and received from him a promise that he should succeed him in England. He married Matilda, daughter of Baldwin V., Count of Flanders, in 1053, though the marriage had been forbidden by the pope on the ground of consanguinity. Lanfranc, Abbot of Bec, reproved him for this marriage, and William ordered him to quit the duchy, but was quickly reconciled, and Lanfranc prevailed on the pope to confirm the marriage, William, as an atonement, building the abbey of St Stephen, and Matilda the abbey of the Holy Trinity, both at Caen. In the next ten years William repulsed two French invasions, and in 1063 conquered the county of Maine. Probably in 1064 Harold, Earl of Wessex, was at his court, and swore to help him to gain the English crown on Edward's death. When, however, Edward died, in 1066, Harold became king. William laid his claim before the pope and western Christendom; he was the last king's kinsman; Edward had promised him the crown; Harold had broken his oath. Warriors joined him from many lands; the pope approved his claim, and by sending him a consecrated banner invested his expedition with something of the character of a crusade. On 14th October he defeated Harold at the battle of Hastings, at a place called by one chronicler Senlac, where he afterwards built Battle Abbey. Harold was slain, and William, having received the submission of the English nobles, was crowned king on 25th December.
England, however, was not yet subdued, and, after a visit to Normandy, William set about completing the conquest. The west and north were subdued in 1068, but the next year the north revolted, and William cruelly devastated the whole country between York and Durham. In 1070 the conquest was completed. The king everywhere confirmed his power by building castles. Although the English generally were allowed to redeem their lands, those who resisted him suffered confiscation. With the confiscated lands he rewarded his followers, granting them to be held of himself, perhaps by military service, though this is contrary to the opinion of some eminent historians. While William made little formal change in the law, the constitution under him assumed a feudal aspect, the old national assembly becoming a council of the king's tenants-in-chief. But he was careful to guard against the evils of continental feudalism; all title to land was originally derived from his grant; he distributed his grants to his great lords over several counties, and in 1086 he exacted an oath of fealty from all landowners, whether holding immediately of him or of other lords. Domesday Book, compiled by his order in that year, contains the record of the land settlement, and of the value of the land for fiscal purposes. The chief result of William's system was a large increase in the power of the crown. He brought the English Church into closer relations with Rome, using the papal authority to forward his own policy with respect to it, while he resisted all interference derogatory to his sovereignty, laying down rules defining the rights of the crown with reference to the papacy, and refusing a demand of homage made by the pope. The intimate union between the church and state in matters of jurisdiction and legislation characteristic of the old English system was abolished, church synods were frequently held, and ecclesiastical causes were removed from the sphere of the lay courts. William's policy, which was ably carried out by Lanfranc, Archbishop of Canterbury, while raising the character of the church, gave the papacy a stronger hold upon it, and tended to endanger the royal authority over it should the throne be occupied by a less capable ruler, or should a dispute arise between the church and the crown. The Conqueror, however, was supreme both in church and state. His rule was stern and orderly; he was greedy of money, and, though not wantonly cruel, careless of human suffering. Passionately fond of hunting, he devastated a large tract in Hampshire to form the New Forest, and heavily punished any breach of his forest laws. All offences were severely dealt with, and mutilation was frequently inflicted, but he forbade capital punishment.
Revolts were made against William both in England and on the Continent. In 1070 there was a rebellion in the Fen Country; the hopes of the rebels were excited by the coming of a Danish fleet, and under the leadership of Hereward they for some time defended the Isle of Ely against the king. English exiles were sheltered by the Scottish king Malcolm, who plundered the northern shires; but William in 1072 crossed the Forth, and compelled Malcolm to make peace and to do him homage at Abernethy. In 1073 he reconquered Maine, which had revolted from him. During his absence in Normandy in 1075 the foreign earls of Hereford and Norfolk rebelled, and a Danish fleet appeared in the Humber. The English, however, were faithful to the king, and the rebellion was quickly suppressed. Walthelof, the English earl of Northumbria, had for a moment been implicated in the plot, and William, who put no one else to death for a political offence, had him beheaded. He made a successful expedition into South Wales, penetrating as far as St Davids. In his later years he engaged without success in some small wars in France. His eldest son, Robert, rebelled against him in Normandy in 1079, defeated and wounded his father at Gerberoi, and went off into France. Having entered on a war with Philip I. of France in 1087, William burned Mantes. As he rode through the burning town his horse stumbled, and he received an injury of which he died at Rouen on 9th September. He left Normandy to his son Robert, declared his wish that his next surviving son William should succeed him in England, and gave his youngest son Henry a sum of money. He was buried in the abbey church that he had built at Caen (q.v.).
See 'William of Poitiers,' 'William of Jumèges,' and 'Orderic,' in Duchesne's Hist. Normann. Script.; Saxon Chronicle, ed. by Plummer; William of Malmesbury's Gesta Regum (Rolls series); Roman de Rou, ed. by Andresen; and modern authors—Freeman's Norman Conquest, ii. iii. iv., and William the Conqueror, in 'Twelve English Statesmen' series; Palgrave's England and Normandy, iii.; Stubbs's Const. Hist., i.; Gneist's Const. Hist., i.; Round's 'Introduction of Knight Service' in Engl. Hist. Rev., Nos. 23, 24, 25. See also BAYEUX TAPESTRY, DOMESDAY, FEUDALISM, HAROLD, HASTINGS, LANFRANC.