England in the Middle Ages son, William, died aboard the "White Ship" disaster of 1120, sparking a fresh succession crisis: Henry's nephew, Stephen of Blois, claimed the throne in 1135, but this was disputed by the Empress Matilda, Henry's daughter. Civil war broke out across England and Normandy, resulting in a long period of warfare later termed the Anarchy. Matilda's son, Henry, finally agreed to a peace settlement at Winchester and succeeded as king in 1154. Henry II was the first of the Angevin rulers of England, so-called because he was also the Count of Anjou in Northern France. Henry had also acquired the huge
Henry I of France William until the former's death in 1060. In 1051, William married Matilda, the daughter of the count of Flanders, which Henry saw as a threat to his throne. In 1054, and again in 1057, Henry invaded Normandy, but on both occasions he was defeated. Henry had three meetings with Henry III, Holy Roman Emperor—all at Ivois. In early 1043, he met him to discuss the marriage of the emperor with Agnes of Poitou, the daughter of Henry's vassal. In October 1048, the two Henries met again and signed a treaty of friendship. The final meeting took place in May 1056