to be challenged in England. In 1139 Matilda and her half-brother, Robert, invaded England. From the age of nine, Henry was repeatedly sent to England to be the male figurehead of the campaigns, since it became apparent that he would become king if England were conquered. In 1141 Stephen was captured at the Battle of Lincoln and later exchanged for Robert, who had also been captured. Geoffrey continued the conquest of Normandy and in 1150 transferred the duchy to Henry while retaining the primary role in the duchy's government. Three events allowed the Angevins' successful termination of the conflict: Count Geoffrey died in 1151 before finalizing the division of his realm between Henry and Henry's younger brother Geoffrey, who would have inherited Anjou. According to William of Newburgh, who wrote in the 1190s, Count Geoffrey decided that Henry would receive England and Anjou for as long as he needed the resources for the conflict against Stephen. Count Geoffrey instructed that his body should not be buried until Henry swore an oath that the young Geoffrey would receive Anjou when England and Normandy were secured. W. L. Warren cast doubt on this account on the grounds that it was written later based on a single contemporary source, it would be questionable that either Geoffrey or Henry would consider such an oath binding and it would break the inheritance practice of the time. The young Geoffrey died in 1158, before receiving Anjou, but he had become count of Nantes when the citizens of Nantes rebelled against their ruler. Henry had supported the rebellion. Louis VII of France was granted an annulment of his marriage to Eleanor of Aquitaine on 18 March 1152, and she married Henry (who would become Henry II) on 18 May 1152. Consequently, the Angevins acquired the Duchy of Aquitaine. Stephen's wife and elder son, Eustace, died in 1153 leading to the Treaty of Wallingford. The treaty agreed the peace offer that Matilda had rejected in 1142, recognised Henry as Stephen's heir, guaranteed Stephen's second son William his father's estates and allowed Stephen to be king for life. Stephen died soon afterwards, and Henry acceded to the throne in late 1154. Angevin zenith Of Henry's siblings, William and Geoffrey died unmarried and childless, but the tempestuous marriage of Henry and Eleanor, who already had two daughters (Marie and Alix) through her first marriage to King Louis, produced eight children