Henry attacked at once. might indeed on that same account look on Henry as an enemy; but such enmity could hardly be decently professed in a treaty of alliance between Robert and William. We may perhaps believe that the chief feeling which the affair of Rouen had awakened in Robert's mind was rather mortification than gratitude. A brother who had acted so vigorously when he himself was not allowed to act at all was dangerous as a neighbour or as a vassal. The memory of his services was humiliating; it was not well to have a brother so near at hand, and in command of so powerful a force, a brother who, if he had at one moment hastened to his elder brother's defence, might at some other moment come with equal speed on an opposite errand. But whatever were their motives, King and Duke agreed to rob their youngest brother of his dominions. And the importance which was attached to this part of the treaty is shown by the speed and energy with which it was carried out. While the recovery of Maine was delayed or forgotten, the recovery of the Côtentin was the first act of the contracting princes after the conclusion of the treaty.
Probable objects of William.
Settlement of the English and Norman succession.
William and Robert to succeed one another.
But, when we look to some other terms of the treaty,
it is possible that, in the mind of William at least, the
spoliation of Henry had a deeper object. One purpose
of the treaty was to settle the succession both to
the kingdom of England and to the duchy of Normandy.
Neither the imperial crown nor the ducal coronet had
at this moment any direct and undoubted heir, according
to any doctrine of succession. Both William and
Robert were at this time unmarried; Robert had more
than one illegitimate child; no children of William Rufus
are recorded at any time. The treaty provided that,
if either King or Duke died without lawful issue during
the lifetime of his brother, the survivor should succeed
