Eustace of Boulogne may refer to one of these four Counts of Boulogne: Eustace I, Count of Boulogne r.1045-1049, son of Count Baldwin II of Boulogne and Adelina of Holland Eustace II, Count of Boulogne (c. 1015-1020 – c. 1087), count of Boulogne from 1049–1087 and companion of William the Conqueror Eustace III, Count of Boulogne, count of Boulogne, son of Eustace II of Boulogne and Ida of Lorraine Eustace IV, Count of Boulogne (c. 1130–1153), Count of Boulogne and son and heir of Stephen of England