His knowledge of canon law, both as a lawyer and cleric, most probably earned him in 1090 the office of Bishop of Chartres, France. His predecessor, Geoffrey, had been removed from office by Pope Urban II. Geoffrey's relatives and supporters initially opposed Ivo's appointment, but with the backing of Pope Urban, King Philip, and the influential Stephen, Count of Blois, Ivo was eventually grudgingly accepted. In light of the events preceding his appointment to the office, his strong opposition to the practice of simony may have been the impetus to his episcopal elevation.