Stephen of Blois

Stephen of Blois (c. 1096 – 1154), a nephew of Henry I, was king of England from 1135. He held vast English estates through his wife Matilda of Boulogne, and the White Ship disaster of 1120, in which Henry's heir drowned, left the succession open to challenge.

On Henry's death in 1135 Stephen seized the throne, breaking his oath to support his daughter, the Empress Matilda. Her 1139 invasion opened the long civil war known as the Anarchy; Stephen was captured at Lincoln in 1141 but later freed. After his own son Eustace died, he recognised Matilda's son Henry as heir by the 1153 Treaty of Winchester, and died in October 1154.