<P> Kenilworth Castle was founded in the early 1120s by Geoffrey de Clinton, Lord Chamberlain and treasurer to Henry I . The castle's original form is uncertain . It has been suggested that it consisted of a motte, an earthen mound surmounted by wooden buildings; however, the stone great tower may have been part of the original design . Clinton was a local rival to Roger de Beaumont, the Earl of Warwick and owner of the neighbouring Warwick Castle, and the king made Clinton the sheriff in Warwickshire to act as a counterbalance to Beaumont's power . Clinton had begun to lose the king's favour after 1130, and when he died in 1133 his son, also called Geoffrey, was only a minor . Geoffrey and his uncle William de Clinton were forced to come to terms with Beaumont; this set - back, and the difficult years of the Anarchy (1135--54), delayed any further development of the castle . </P> <P> Henry II succeeded to the throne at the end of the Anarchy but during the revolt of 1173--74 he faced a significant uprising led by his son, Henry, backed by the French crown . The conflict spread across England and Kenilworth was garrisoned by Henry II's forces; Geoffrey II de Clinton died in this period and the castle was taken fully into royal possession, a sign of its military importance . The Clintons themselves moved on to Buckinghamshire . By this point Kenilworth Castle consisted of the great keep, the inner bailey wall, a basic causeway across the smaller lake that preceded the creation of the Great Mere, and the local chase for hunting . </P> <P> Henry's successor, Richard I, paid relatively little attention to Kenilworth, but under King John significant building resumed at the castle . When John was excommunicated in 1208, he embarked on a programme of rebuilding and enhancing several major royal castles . These included Corfe, Odiham, Dover, Scarborough as well as Kenilworth . John spent £ 1,115 on Kenilworth Castle between 1210 and 1216, building the outer bailey wall in stone and improving the other defences, including creating Mortimer's and Lunn's Towers . He also significantly improved the castle's water defences by damming the Finham and Inchford Brooks, creating the Great Mere . The result was to turn Kenilworth into one of the largest English castles of the time, with one of the largest artificial lake defences in England . John was forced to cede the castle to the baronial opposition as part of the guarantee of the Magna Carta, before it reverted to royal control early in the reign of his son, Henry III . </P> <P> Henry III granted Kenilworth in 1244 to Simon de Montfort, Earl of Leicester, who later became a leader in the Second Barons' War (1263--67) against the king, using Kenilworth as the centre of his operations . Initially the conflict went badly for King Henry, and after the Battle of Lewes in 1264 he was forced to sign the Mise of Lewes, under which his son, Prince Edward, was given over to the rebels as a hostage . Edward was taken back to Kenilworth, where chroniclers considered he was held in unduly harsh conditions . Released in early 1265, Edward then defeated Montfort at the Battle of Evesham; the surviving rebels under the leadership of Henry de Hastings, Montfort's constable at Kenilworth, regrouped at the castle the following spring . Edward's forces proceeded to lay siege to the rebels . </P>

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