Enguerrand I of Ponthieu

Enguerrand I was the son of Hugh I of Ponthieu and probably Gisela, daughter of Hugh Capet.

He was apparently married twice. By his first wife Adelaide, daughter of Arnulf, Count of Holland he had his heir, count Hugh II, and possibly a son named Robert (although Robert might have been a younger half-brother of Hugh II's). His other sons, Guy, Bishop of Amiens and Fulk (later abbot of Forest l'Abbaye), were evidently sons by the second wife. She has been identified as the wife of a count Arnold II of Boulogne who died in battle against Enguerrand I. He was in his forties when he took the widow of his erstwhile enemy to wife.

Enguerrand died around 1045 "at a great age."

...
Wikipedia