967-c.1000 : Gilbert of Roucy, count of Roucy and viscount of Reims († v.1000), son of the former
No document of the era mentions the relationship between Gilbert and his successor Ebles I. It has long been thought that Ebles of Roucy was a son of Gilbert and of a daughter of William III, Duke of Poitiers.
A recent study proposed another theory : Ebles I of Roucy was a son of Ebles of Poitiers (himself the son of William IV, Duke of Poitiers and of Emma of Blois) and of a daughter of Aubry II, count of Mâcon, and of Ermentrude of Roucy, sister of Gilbert of Roucy.
^Jean-Noël Mathieu, "La Succession au comté de Roucy aux environs de l'an mil", in Onomastique et Parenté dans l'Occident médiéval, under the direction of Christian Settipani and Katharine S. B. Keats-Rohan, 2000