The town was taken by assault, and William kept his oath.  The castle held out; the hands and feet of thirty-two pollarded burghers of Alencon were thrown over its walls, and the threat implied drove the garrison to surrender on promise of safety for life and limb.  The defenders of Domfront, struck with fear, surrendered also, and kept their arms as well as their lives and limbs.  William had thus won back his own rebellious town, and had enlarged his borders by his first conquest.  He went farther south, and fortified another castle at Ambrieres; but Ambrieres was only a temporary conquest.  Domfront has ever since been counted as part of Normandy.  But, as ecclesiastical divisions commonly preserve the secular divisions of an earlier time, Domfront remained down to the great French Revolution in the spiritual jurisdiction of the bishops of Le Mans.

William had now shown himself in Maine as conqueror, and he was before long to show himself in England, though not yet as conqueror.  If our chronology is to be trusted, he had still in this interval to complete his conquest of his own duchy by securing the surrender of Brionne; and two other events, both characteristic, one of them memorable, fill up the same time.  William now banished a kinsman of his own name, who held the great county of Mortain, Moretoliam or Moretonium, in the diocese of Avranches, which must be carefully distinguished from Mortagne-en-Perche, Mauritania or Moretonia in the diocese of Seez.  This act, of somewhat doubtful justice, is noteworthy on two grounds.  First, the accuser of the banished count was one who was then a poor serving-knight of his own, but who became the forefather of a house which plays a great part in English history, Robert surnamed the Bigod.  Secondly, the vacant county was granted by William to his own half-brother Robert.  He had already in 1048 bestowed the bishopric of Bayeux on his other half-brother Odo, who cannot at that time have been more than twelve years old.  He must therefore have held the see for a good while without consecration, and at no time of his fifty years’ holding of it did he show any very episcopal merits.  This was the last case in William’s reign of an old abuse by which the chief church preferments in Normandy had been turned into means of providing for members, often unworthy members, of the ducal family; and it is the only one for which William can have been personally responsible.  Both his brothers were thus placed very early in life among the chief men of Normandy, as they were in later years to be placed among the chief men of England.  But William’s affection for his brothers, amiable as it may have been personally, was assuredly not among the brighter parts of his character as a sovereign.