The Welsh had taken advantage of the king's difficulties to invade the adjoining counties, and "after their accustomed manner,"[9] carried off the cattle, and plundered and murdered the inhabitants, many of whom they also made prisoners. They laid siege to the castle of Montgomery, and took it by assault, slaying all the garrison. William in 1095 marched hastily into Wales, but found it impossible to reach the marauders, who kept to the cover of the woods and marshes, and among the mountains, watching their opportunity to slay any of the English and Norman troops whom they could reach unawares. Rufus pursued them over the hills; but his march was attended with heavy loss to his army, and he was at length compelled to retreat, "not without some note of dishonour." Two other expeditions met with no better success. Thereupon he left the conquest of Wales to his nobles, whose eagerness was whetted by grants of land in the unconquered districts. An army was despatched under the command of the Earl of Shrewsbury, and the Earl of Chester, who re-took the isle of Anglesea, of which the Welsh had obtained possession.[10] The inhabitants were maltreated or put to the sword; but, having received some reinforcements, a battle ensued, in which the Earl of Shrewsbury was slain. The victory, however, was on the side of the Earl of Chester, who remained for some time in Wales, desolating the country.

While the Welsh were still unsubdued, Rufus received information of a powerful confederacy which had been formed against him in the north of England. The king had reason to suspect some of his nobles of disaffection, and especially Robert Mowbray, Earl of Northumberland, a powerful noble, whose long absence from court had excited suspicion. A royal proclamation was issued, calling upon every baron in the kingdom to appear at court at the approaching festival of Whitsuntide, on pain of outlawry. The Earl of Northumberland neglected to obey the summons, and the king immediately marched an army to Newcastle, where he surprised some of the earl's accomplices. He next besieged and took the castle of Tynemouth, and thence proceeded to Bamborough, an impregnable fortress, to which the Earl had retreated with his family.

After various unsuccessful attempts to take this castle by storm, Rufus, who seems to have inherited much of the military talent of his father, adopted another plan of attack. He built a wooden fort opposite Bamborough, calling it Malvoisin, or "bad neighbour"; and, having placed a garrison in it, he withdrew the rest of his army. His lieutenants were directed to use every opportunity of inflicting damage upon the adherents of Earl Mowbray, or of gaining possession of his person.

One night the earl quitted his castle with an escort of only thirty horsemen. The object with which he did so is variously stated; but the most probable account is that he was betrayed by some followers of Rufus, who offered to give up the town of Newcastle into his possession. The earl was surprised by a body of Norman troops, and while many of his retinue were cut to pieces, he escaped from his assailants, and took sanctuary at St. Oswin's monastery, Tynemouth. By the laws of chivalry, the blackest criminal was safe under the shadow of the Cross; but the soldiers of William were deterred neither by those laws, nor by any respect for the sacredness of the place. They pursued the earl to his sanctuary, and after a desperate resistance made him prisoner.

Having carried Earl Mowbray to Bamborough, and placed him before the gates of his castle, they demanded a parley with the Countess Matilda. On her appearance, they exhibited her husband as a prisoner, and told her that they would put out his eyes before her face unless she at once gave up the castle into their hands. Matilda is described as having been remarkable for her beauty; she was young, and had been married to the earl only a few months before. She did not long hesitate, but ordered the gates to be thrown open. Among the followers of Mowbray was one through whom Rufus gained a knowledge of the extent of the conspiracy, and of the persons implicated in it. The subsequent fate of Mowbray was that of a living death. His young wife had indeed saved him from blindness, but he was not the less deprived of the light of day. Condemned to perpetual imprisonment, he was confined in a dungeon at Windsor Castle, where we read that he dragged on existence for thirty years afterwards. Another account, however, has it that he ended his life as a monk.

The property of the banished nobles was plundered by the adherents of the king, and then left for some time uncultivated, and without owners. Nevertheless, the people of the town or hundred in which such estates lay, were compelled to pay the full amount of land tax as before. The king, also, forcibly raised troops of men to build a wall encircling the Conqueror's Tower at London, a bridge over the Thames, and, near the West Minster, a hall or palace of audiences, for the stated assemblies or assizes of the great barons.[11]

The money which William Rufus paid to his brother for the possession of Normandy was obtained by inflicting new burdens and exactions upon his people. "All this," says Holinshed, "was grievous and intolerable, as well to the spirituality as temporality, so that divers bishops and abbesses, who had already made away with some of their chalices and church jewels to pay the king, made now plain answer that they were not able to help him with any more; unto whom, on the other side, as the report went, the king said again, 'Have you not, I beseech you, coffins of gold and silver, full of dead men's bones?' meaning the shrines in which the relics of saints were enclosed."

The king also argued that there was no sacrilege in taking money obtained from such a source, for the purpose of prosecuting a holy war, and delivering the sepulchre of Christ from the hands of the infidel. He did not choose to remember that the expedition to the Holy Land was one in which he had no part, and that he required the money, not for that purpose, but to obtain a worldly possession. If the argument carried little weight, the force by which it was backed was not to be resisted, and the spoils of the altar, as well as the hoards of civilians, were seized in the king's name.

Robert, having resigned his dukedom, and set out for the Holy Land, William passed over into Normandy to take possession. He was received with welcome by the Norman nobles, who, if not well disposed towards their new sovereign were overawed by his power or bought by his gold. The people of Maine, however, rose in revolt, and, headed by Helie, the Lord of La Flèche, the insurrection assumed an importance which rendered it necessary for Rufus to take energetic measures for its repression. He entered Maine at the head of a large force, but on the interference of the Count of Anjou and Philip of France, he consented to a truce with the insurgents, and Helie, having been taken prisoner, was set at liberty, on tendering his submission, and giving up of Le Mans into the king's hands. (A.D. 1099.)

The people, however, remained disaffected towards the English king. A year passed away without any change in this state of things, when one day, as William was hunting in the New Forest, a messenger came to him with the intelligence that Helie had obtained possession of the town of Le Mans, that the inhabitants had joined him, and were besieging the castle, containing the Norman garrison. Rufus immediately set off for the sea-coast without waiting for an escort; and when some of his lords came up with him, as he was about to embark, they counselled him to wait until troops could be summoned to accompany him. William replied, "Such as love me, I know well, will follow me," and went at once on shipboard. A storm was blowing so violently that even the sailors hesitated to set sail; but the king was determined to proceed, and cried out to the master to weigh anchor, asking him if he had ever heard of a king that was drowned?