Eustace IV ruled the County of Boulogne from 1146 until his death. He was the eldest son of King Stephen of England and Countess Matilda I of Boulogne. When his father seized the English throne on Henry I's death in 1135, he became heir apparent... Wikipedia
Born: 1130
Died: August 17, 1153 (age 23 years), Bury St Edmunds, United Kingdom
Parents: Stephen of England and Matilda I, Countess of Boulogne
Spouse: Constance of France, Countess of Toulouse (m. 1140)
Reign: 25 December 1146 – 17 August 1153