The Genealogica comitum Buloniensium records that "Eustachium et Lantbertum" were sons of "comes Eustachius de Bolonia" and his wife Mathilde. His birth date range is estimated from the date of his first marriage, and bearing in mind the estimated birth date range of his mother.
He succeeded his father in [1049] as Comte de Boulogne. Simeon of Durham records that "Eustace the elder earl of Boulogne who had married king Eadward's sister Goda" landed at Dover in Sep 1051. When returning from visiting Edward "the Confessor" King of England in 1051, he was involved in an affray at Canterbury during which one of his men was killed. The refusal of Godwin Earl of Wessex to punish the offenders led to the Earl's temporary banishment from England.
Comte de Lens 1054. "Eustatii comitis" witnessed a charter of "Balduinus Flandrensium comes" dated 6 Jan 1056. Orderic Vitalis records that “Eustachium comitem” was seriously wounded during the battle of Hastings but escaped “quasi moribundus”. He was awarded a large fief "the honour of Boulogne", but soon quarrelled with William I King of England. He launched an attack on England in 1067, but withdrew after landing. His English lands were confiscated, but later restored. Boulogne's strategic importance grew as it became the main port for importing English wool for the Flemish cloth trade. 2