( c. 1208–65)
an English politician and soldier, the leader of the barons who opposed Henry III . After being defeated in battle in 1264, he lost the support of the other barons because he wanted to rule the country himself. In 1265, he appointed himself head of government and formed his own parliament in London. The same year he was killed when fighting at the Battle of Evesham against an army led by Henry III’s son, who later became Edward I .