Such were the mighty alterations which already had fully taken place, or were gradually advancing, in the house of peers; that is, in the parliament: for there seems anciently to have been no other house.
* Spel.

Gloss, in voce Comes.
** Essays on British Antiquities.

This practice, however, seems to have been more familiar in Scotland and the kingdoms on the continent, than in England.
*** There are instances of princes of the blood who accepted of the office of sheriff.Spel.in voce Vicecomes.
But though the introduction of barons by writ, and of titular earls, had given some increase to royal authority, there were other causes which counterbalanced those innovations, and tended in a higher degree to diminish the power of the sovereign.

The disuse into which the feudal militia had in a great measure fallen made the barons almost entirely forget their dependence on the crown: by the diminution of the number of knights' fees the king had no reasonable compensation when he levied scutages, and exchanged their service for money: the alienations of the crown lands had reduced him to poverty: and above all, the concession of the Great Charter had set bounds to royal power, and had rendered it more difficult and dangerous for the prince to exert any extraordinary act of arbitrary authority.

In this situation it was natural for the king to court the friendship of the lesser barons and knights, whose influence was no ways dangerous to him, and who, being exposed to oppression from their powerful neighbors, sought a legal protection under the shadow of the throne.