No greater piece of good luck could have befallen the duke than to win the post of Harold's benefactor, and he played the part gallantly. Not only the duke but the duchess treated their guest with [Pg265] uncommon courtesy, and he was admitted to the closest intimacy with the household. If Harold had been wise he would have gone back to England as fast as sails could carry him, but instead of that he lingered on, equally ready to applaud the Norman exploits in camp and court, and to show his entertainers what English valor could achieve. He went with the duke on some petty expedition against the rebellious Britons, but it is hard to make out a straight story of that enterprise. But there is a characteristic story of Harold's strength in the form of a tradition that when the Norman army was crossing the deep river Coesnon, which pours into the sea under the wall of Mount St. Michel, some of the troops were being swept away by the waves, when [Pg266] Harold rescued them, taking them with great ease, at arm's length, out of the water.
There is a sober announcement in one of the old chronicles, that the lands of Brittany were included in Charles the Simple's grant to Rolf, because Rolf had so devastated Normandy that there was little there to live upon. At the time of William's expedition, Brittany itself was evidently taking its turn at such vigorous shearing and pruning of the life of its fertile hills and valleys. The Bretons liked nothing so well as warfare, and when they did not unite against a foreign enemy, they spent their time in plundering and slaughtering one another. Count Conan, the present aggressor, was the son of Alan of Brittany, William's guardian. Some of the Bretons were loyal to the Norman authority, and Dôl, an ancient city renowned for its ill luck, and Dinan were successively vacated by the rebels. Dinan was besieged by fire, a favorite weapon in the hands of the Normans; but later we find that both the cities remained Breton, and the Norman allies go back to their own country. There is a hint somewhere of the appearance of an army from Anjou, to take the Bretons' part, but the Norman chroniclers ignore it as far as they can.
It is impossible to fix the date of this campaign; indeed there may have been more than one expedition against Brittany. Still more difficult is it to learn any thing that is undisputed about the famous oath that Harold gave to William, and was afterward so completely punished for breaking. Yet, while we do not know exactly what the oath was, [Pg267] Harold's most steadfast upholders have never been able to deny that there was an oath, and there is no contradiction, on the English side, of the whole affair. His best friends have been silent about it. The most familiar account is this, if we listen to the Norman stories: Harold entered into an engagement to marry one of William's daughters, who must have been very young at the time of the visit or visits to Normandy, and some writers claim that the whole cause of the quarrel lay in his refusal to keep his promise. There is a list beside of what appears to us unlikely concessions on the part of the English earl. Harold did homage to the duke, and formally became his man, and even promised to acknowledge his claim to the throne of England at the death of the Confessor. More than this, he promised to look after William's interest in England, and to put him at once into possession of the Castle of Dover, with the right of establishing a Norman garrison there. William, in return, agreed to hold his new vassal in highest honor, giving him by and by even the half of his prospective kingdom. When this surprising oath was taken, Harold was entrapped into swearing upon the holiest relic of Norman saints which had been concealed in a chest for the express purpose. With the superstitious awe that men of his time felt toward such emblems, this not very respectable act on William's part is made to reflect darkly upon Harold. Master Wace says that "his hand trembled and his flesh quivered when he touched the chest, though he did not know what was in it, and how much more distressed he was when he [Pg268] found by what an awful vow he had unwittingly bound his soul."