Eustace IV, Count of Boulogne Eustace IV, Count of Boulogne Eustace IV (c. 1127–1135 – 17 August 1153), Count of Boulogne, 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 to the English throne. Upon his mother's death in 1152 he inherited the county of Boulogne and other estates. Eustace was first mentioned in one of his parents' charters dated no later than August 1131. As heir to the English throne in 1137, he did homage for Normandy to Louis VII of
History of the English line of succession Prince Louis of France as king. However, with John's death, his barons saw his young son as a safer option. John's eldest son became Henry III, and the French were driven away from the country. On Henry III's death, on 16 November 1272, the throne passed to his eldest son, Edward I. On Edward I's death, on 7 July 1307, the throne passed to his eldest son, Edward II. On the day of Edward II's abdication, 25 January 1327, the throne passed to his eldest son, Edward III. The succession to Edward III was governed according to his entail to