What type of surety was the Earl of Pembroke who participated in the battle at Lincoln castle in 1217?
William Marshal, 2nd Earl of Pembroke: William Marshal, 2nd Earl of Pembroke (French:"Guillaume") (1190 – 6 April 1231) was a medieval English nobleman and was one of Magna Carta sureties. Battle of Lincoln (1217): The Second Battle of Lincoln occurred at Lincoln Castle on Saturday 20 May 1217, during the First Barons' War, between the forces of the future Louis VIII of France and those of King Henry III of England.
Magna Carta