The great lay lords of the late tenth and eleventh centuries were at once co-operative and predatory. The Anglo-Scandinavian and Norman aristocrats who fought for the king, represented him in the hundred and shire courts, and witnessed his solemn diplomas were also fully capable of practising an extravagant and self-interested hooliganism to improve their own standing in the world. Many, like the damned crowd, the familia Herlechini, encountered by Orderic Vitalis's priest of Bonneval, not only fought for the king, but at one time or another carried ‘across their necks and shoulders animals and clothes, and every kind of furnishing and household goods that raiders usually seize as plunder’. They did serve the king, but when given the opportunity they grasped what they could for themselves. When the desires of these enterprising bully boys, their kinsmen, and their hangers-on were the same as those of the king (sometimes a kinsman and a bully himself), the results, institutionally and politically, could be impressive. Such co-operation produced many of the glories of Edgar the Peaceable's reign and William the Conqueror's rule. But the mix of king and powerful aristocrats with a localized administration was a volatile one. When the interests of the Rex Anglorum and his greatest aristocrats were no longer in harmony, or if the wealth of important men began to eclipse that of the king, there could be a rapid dissolution of royal power.

Many of the wonders of tenth- and eleventh-century England have been credited to its kings.