At the height of his power and influence the justiciar was the king's chief political and judicial officer, superintending the administrative machinery and acting as regent in the king's absence abroad. He was also a feudal lord or bishop; and the study of the careers of the chief justiciars, as soldiers and politicians, judges and financiers, throws light on the workings of feudal society and on the technical administrative means by which royal power was effectively exercised. Dr West traces the history of the office from the first need for the delegation of royal power under William 1 until...