Battle of Lewes

The Battle of Lewes was one of two main battles of the conflict known as the Second Barons' War. It took place at Lewes in Sussex, on 14 May 1264. It marked the high point of the career of Simon de Montfort, 6th Earl of Leicester, and made him the "uncrowned King of England". Henry III left the safety of Lewes Castle and St. Pancras Priory to engage the Barons in battle and was initially successful, his son Prince Edward routing part of the baronial army with a cavalry charge. However Edward pursued his quarry off the battlefield and left Henry's men exposed. Henry was forced to launch an infantry attack up Offham Hill where he was defeated by the barons' men, defending the hilltop. The royalists fled back to the castle and priory and the King was forced to sign the Mise of Lewes, ceding many of his powers to Montfort.

Henry III was an unpopular monarch due to his autocratic style, displays of favouritism and his refusal to negotiate with his barons. The barons eventually imposed a constitutional reform known as the Provisions of Oxford upon Henry that called for a thrice-yearly meeting led by Simon de Montfort to discuss matters of government. Henry sought to escape the restrictions of the provisions and applied to Louis IX of France to arbitrate in the dispute. Louis agreed with Henry and annulled the provisions. Montfort was angered by this and rebelled against the King along with other barons in the Second Barons' War.

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