Yves inherited a chaotic situation around 1047/8, as his brother had become entangled in a conflict with the family of Giroie, and a revolt from his son Arnulf had overthrown him.
Arnulf himself was soon murdered and Ivo, being the only remaining male in the direct line, assumed both the bishopric of Sées and the lordship of Bellême.
[5] During his episcopate, he privileged peaceful relations with his neighbors, as can be appreciated from charter evidence linking him to Rotrou I, Viscount of Châteaudun, [7] and his presence in the courts of the Norman dukes, Angevin counts and French kings.
Orderic Vitalis, usually quite hostile to the House of Bellême, presents a very positive assessment of Ivo: learned and spiritual, shrewd, eloquent and peace-loving.
As a modern author has written, he was one of the last old-fashioned bishops, heavily involved in secular affairs, and in that respect close to Odo of Bayeux and Geoffrey de Montbray.