“Ivo...Belmontensis castri comes” donated property to la Trinité de Fécamp by charter dated to after 1027, subscribed by “Ivonis comitis, [J]osfredi filii eius, Ivonis clerici eius filii sui fratris, Alberici eius filii”. "Comes Ivo cum filio meo simili nomine…clerico et canonico…cum mea propria conjuge Emma et ceteris omnibus meis liberis" donated "castrum Confluentie" to Saint-Wandrigisel by charter dated 1039, signed by "Ivo…comes…Ivo clericus…comes Goffredus, Albericus, Gelduini vicecomitis…Odonis filii supradicti comitis, Gosberti fratris eiusdem Odonis". Ives must have resigned his ecclesiastical appointments soon after the date of this charter, as the following sources do not mention his church positions and because the birth of his daughter can be estimated to [before 1045] (see below). "…Ivonis filii Ivonis comitis de Bello Monte…" witnessed a charter dated to [1042/44] under which "Guanilo thesaurarius Sancti Martini" donated property to Marmoutier. "…Yvonis filii Yvonis comitis…" subscribed the charter dated to [1049/60] which records the agreement between the abbey of Monmajour and Chartres Notre-Dame.
Comte de Beaumont-sur-Oise. The identity of Ives [II] Comte de Beaumont as the son of Comte Ives [I] is confirmed by the undated charter under which “comes Matheus...laudantibus conjuge mea Aeles et liberis meis” [Mathieu [II] Comte de Beaumont] confirmed the exemption from navigation duties to the monks of Saint-Wandrille de Fontenelle granted by “Ivo comes cum filio suo simile nomine scilicet clerico et canonico, cui jure hereditario post discessus sui cursum castrum Confluencie tribuendo concessit, cum sua propria conjuge Emma...” "…Ivonis comitis Belli Montis…" subscribed the charter dated 1071 under which "Buccardus…Corbolensium comes" donated property to the abbey of Saint-Spire de Corbeil.
He founded Conflans Sainte-Honorine in 1080: “Ivo comes de Bellomonte et Adelhidis uxor eius” donated “ecclesia Sanctæ Honorinæ de Confluencio” to the monastery of Bec by charter dated 1080. The Chronicon Beccensis Abbatiæ records that "Yvo de Bellomonte comes uper Isarum et Adelidis uxor eius" donated "ecclesia B. Honorinæ de Confluentium” to Bec in 1082. "Mainerium, fratrem Symonis de Monte Forti" donated property, with the consent of "Simone fratre eius comiteque Belli Montis Ivonis", by charter dated to before 1091, which also names "domnus Simon, filio suo Amalrico".
The necrology of Beaumont Saint-Léonor records the death “XI Kal Jun” of “Iuo comes qui adstruxit ecclesiam Sancti Leonorii”. 2