House of Blois chose a wife from the House of Champagne (Adela of Champagne) as a counterpoise to Angevin power. The senior line of the House of Blois became extinct with the death of Joan I of Navarre, wife of Philip IV of France, in 1305. Champagne and Navarre passed to the Capetian dynasty. King Stephen I of England, 1135–1154, was both a member of the House of Blois and the last Anglo-Norman King, being the grandson of William the Conqueror through his daughter Adela of Normandy. A branch of the family was established in Sancerre by Stephen I of Sancerre, a younger
Stephen, King of England time. On this occasion, however, William Martel, Stephen's steward, made a fierce rear guard effort, allowing Stephen to escape from the battlefield. Stephen valued William's loyalty sufficiently to agree to exchange Sherborne Castle for his safe release—this was one of the few instances where Stephen was prepared to give up a castle to ransom one of his men. In late 1143, Stephen faced a new threat in the east, when Geoffrey de Mandeville, the Earl of Essex, rose up in rebellion against the King in East Anglia. Stephen had disliked the baron for several years, and provoked the conflict by