Research Notes:

"Willelmus comes" donated property to Cluny by charter dated 28 Aug [990] signed by "Rodbaldus comes, Adalaix comitissa, Wilelmus comes et filius eius Wilelmus". "Dominus princeps et marchio istius provinciæ…Willelmus cum coniuge sua…Adelaix et filio suo…Willelmo" restored property to the abbey of Saint-Césaire d´Arles by charter dated 992, subscribed by "Domnus Rotbaldus comes…Willelmus comes filius Rotbaldi et uxor sua Lucia, Wilelmus comes Tolosanus et uxor sua Ema…". According to Europäische Stammtafeln, he was the son of Comte Guillaume by his first wife but the primary source on which this is based has not been identified. It is probably speculative, based on his marriage date, which suggests that he was born earlier than the date of his father's second marriage. In any case, Guillaume's parentage appears to be proved by the charter dated 1005 quoted below.

He succeeded his father in 992 as Comte de Provence. "Pontius…Massiliensis ecclesie pontifex" issued a charter dated 1005 with the consent of "domni Rodhbaldi comitis et domne Adalaizis comitisse, domnique Guillelmi comitis filii eius". "Wilelmus comes Provincie conjuxque mea Girberga cum filio nostro...Wilelmo" donated "in comitatu Sisterico, intra terminos de villa…Manuasca" to Marseille Saint-Victor by charter dated 1013, subscribed by “Wilelmus comes Provincie...domna Guirberga...comitissa, domnus Wilelmus eorum...soboles, Guillelmus vicecomes, Fulco frater eius, Accelena et Odila, Villelmus filius Villemi...”. ¹