In the five years after 1197, Peter des Roches had established himself in a prominent position amongst the clerks of the royal chamber. He enjoyed the confidence of King John, by whom he had been promoted to various churches in Anjou, Poitou and the Touraine. Altogether, his career seemed launched on a steady course. But appearances were deceptive. The Plantagenet dominion over north and western France, established a mere fifty years before, was coming increasingly under strain. Since the mid-1190s, much of Normandy had been plunged into near constant warfare between the Plantagenets and the Capetian kings of France. By employing mercenaries within what had once been areas of relative peace, away from the Franco-Norman frontier, John forfeited much of the sympathy that his family had previously commanded amongst the Norman baronage. At the same time, employing his titular claim to overlordship within most of the Plantagenet lands, the French king, Philip Augustus, was able further to undermine the relations between John and his subjects in France. The death of King Richard I in 1199 enabled Philip to exploit the dispute over the Plantagenet succession that erupted between John and his nephew, Arthur of Brittany. Added to this, by his skilful management of the Capetian demesne, Philip was by 1200 a richer king than John, better able to meet the costs of war. In 1202 John scored a notable military breakthrough at Mirebeau. Arthur was taken prisoner. But John's success was short-lived. Within a matter of months Arthur was dead, in all likelihood murdered by John, or at John's direct command: an act of brutality that was to shatter John's fragile reputation throughout the Plantagenet lands.