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
Henry Borwin I, Lord of Mecklenburg Lion in Lüneburg, and Henry Borwin I succeeded him as Lord of Mecklenburg. Shortly before Pribislav's death, Henry Borwin I married Matilda, a daughter of Henry the Lion. For several years, Henry Borwin I fought a war with his cousin Nicholas I. His father-in-law was unable to assist him during this war. This lack of outside assistance attracted the attention of King Canute VI of Denmark, who used the situation to expand his position on the Baltic Sea coast. The Danes took Henry Borwin I prisoner. He had to cede Rostock to Denmark and accept Canute VI as his liege