Eustache of Boulogne was a notable figure from the 11th century, recognized for his role as a nobleman and military leader. He was the son of Eustace I, Count of Boulogne and played a significant part in the First Crusade, which aimed to reclaim the Holy Land from Muslim control. Eustache was known for his bravery and leadership during the campaign. He is often remembered for his contributions to the Crusader states established in the Levant after the successful siege of Jerusalem in 1099. Eustache's legacy is intertwined with the broader history of the Crusades and the interactions between Christian and Muslim cultures during this period.