De Montfort Rebellion

Second Barons' War
Date 1264–1267 Location England Result Initial baronial success, Royalist victory
Belligerents
Royal forces	Baronial forces
Commanders and leaders
Henry III of England Prince Edward Queen Eleanor	Simon de Montfort  † and other barons

The Second Barons' War (1264–1267) was a civil war in England between the forces of a number of barons led by Simon de Montfort against Royalist forces led by Prince Edward (later Edward I of England), in the name of Henry III.

The reign of Henry III is most remembered for the constitutional crisis in this period of civil strife, which was provoked ostensibly by Henry III's demands for extra finances, but which marked a more general dissatisfaction with Henry's methods of government on the part of the English barons, discontent which was exacerbated by widespread famine.

French-born Simon de Montfort, Earl of Leicester, had originally been one of the foreign upstarts so loathed by many lords as Henry's foreign councillors, but having inherited through his mother the English title Earl of Leicester, he married Henry’s sister Eleanor without Henry's permission, and without the agreement of the English Barons (ordinarily necessary since it was a matter of state). As a result, a feud developed between de Montfort and Henry. Their relationship reached a crisis in the 1250s, when de Montfort was put on trial for actions he took as lieutenant of Gascony, the last remaining Plantagenet lands across the English Channel.

Henry also became embroiled in funding a war against the Hohenstaufen Dynasty in Sicily on behalf of Pope Innocent IV in return for the Hohenstaufen title King of Sicily for his second son Edmund. This made many barons fearful that Henry was following in the footsteps of his father King John and, like him, needed to be kept in check. When Henry's treasury ran dry, Innocent withdrew the title, and in regranting it to Charles of Anjou in effect negated the sale.

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