The three princes, residing with their father in the castle of L’Aigle, in Normandy, were one day engaged in sport together, and after some mirth and jollity, the two younger took a fancy of throwing over some water on Robert as he passed through the court on leaving their apartment;[***] a frolic which he would naturally have regarded as innocent, had it not been for the suggestions of Alberic de Grentmesnil, son of that Hugh de Grentmesnil whom William had formerly deprived of his fortunes, when that baron deserted him during his greatest difficulties in England. The young man, mindful of the injury, persuaded the prince that this action was meant as a public affront, which it behoved him in honor to resent; and the choleric Robert, drawing his sword, ran up stairs, with an intention of taking revenge on his brothers.[****]
[* Order. Vitalis, p. 545. Hoveden, p. 457. Flor. Wigorn. p. 639.]
The whole castle was filled with tumult, which the king himself, who hastened from his apartment, found some difficulty to appease. But he could by no means appease the resentment of his eldest son who, complaining of his partiality, and fancying that no proper atonement had been made him for the insult, left the court that very evening, and hastened to Rouen, with an intention of seizing the citadel of that place.[*] But being disappointed in this view by the precaution and vigilance of Roger de Ivery, the governor, he fled to Hugh de Neufchatel, a powerful Norman baron, who gave him protection in his castles; and he openly levied war against his father.[**] The popular character of the prince, and a similarity of manners, engaged all the young nobility of Normandy and Maine, as well as of Anjou and Brittany, to take part with him: and it was suspected that Matilda, his mother, whose favorite he was, supported him in his rebellion by secret remittances of money; and by the encouragement which she gave his partisans.
[** Order. Vitalis, p. 545. Hoveden, 457, Sim. Dunelm. p. 210. Diceto, p. 487]
All the hereditary provinces of William, as well as his family, were during several years thrown into convulsions by this war; and he was at last obliged to have recourse to England, where that species of military government, which he had established, gave him greater authority than the ancient feudal institutions permitted him to exercise in Normandy. He called over an army of English under his ancient captains, who soon expelled Robert and his adherents from their retreats, and restored the authority of the sovereign in all his dominions. The young prince was obliged to take shelter in the castle of Gerberoy, in the Beauvoisis, which the king of France, who secretly fermented all these dissensions, had provided for him. In this fortress he was closely besieged by his father, against whom having a strong garrison, he made an obstinate defence. There passed under the walls of this place many rencounters which resembled more the single combats of chivalry than the military actions of armies; but one of them was remarkable for its circumstances and its event. Robert happened to engage the king, who was concealed by his helmet, and, both of them being valiant, a fierce combat ensued, till at last the young prince wounded his father in the arm and unhorsed him. On his calling out for assistance, his voice discovered him to his son, who, struck with remorse for his past guilt, and astonished with the apprehensions of one much greater, which he had so nearly incurred, instantly threw himself at his father’s feet, craved pardon for his offences, and offered to purchase forgiveness by any atonement.[*] The resentment harbored by William was so implacable, that he did not immediately correspond to this dutiful submission of his son with like tenderness; but, giving him his malediction, departed for his own camp, on Robert’s horse, which that prince had assisted him to mount, He soon after raised the siege, and marched with his army to Normandy; where the interposition of the queen and other common friends brought about a reconcilement, which was probably not a little forwarded by the generosity of the son’s behavior in this action, and by the returning sense of his past misconduct. The king seemed so fully appeased that he even took Robert with him into England, where he intrusted him with the command of an army, in order to repel an inroad of Malcolm, king of Scotland, and to retaliate by a like inroad into that country. The Welsh, unable to resist William’s power, were, about the same time, necessitated to pay a compensation for their incursions; and every thing was reduced to full tranquillity in this island.