Gerberga, Otto-William's mother[1] (c. 947[2] – 986/91), was, by her successive marriages, queen of Italy (c. 958 – 963), margravine of Ivrea (965–970), and duchess of Burgundy (971/5–986/91).
[3][4] Because Gerberga's son, Otto-William, later succeeded to the county of Mâcon (through marriage to Ermentrude de Roucy, the widow of the previous count), old assumptions had mistakenly argued that Gerberga must have been descended from the counts of Mâcon rather[5] than from Lambert of Chalon or Adelaide.
[7] The scenario where Adelaide is the common mother may explain[8] that on the death without direct heirs in 1039 of Gerberga's brother Hugh, his county of Chalon which come from Lambert, was inherited by children of his younger sister Mathilde, ignoring the superior claims of Gerberga's own descendants, among whom were the powerful counts of Burgundy.
[10] After Adalbert's death in 971/5, Gerberga married for a second time, to Henry I, Duke of Burgundy, the younger brother of King Hugh Capet.
Otto-William become count of this district before 991, and after 1005[14] he will donate the villa of Veuvey-sur-Ouche, which belonged to his mother, to the Abbey St. Bénigne in Dijon.