Second Barons' War: Royal troops led by Prince Edward defeated baronial forces under Simon de Montfort at the Battle of Evesham in Worcestershire, England.

The Second Barons' War (1264–1267) was a civil war in England between the forces of barons led by Simon de Montfort against the royalist forces of King Henry III, led initially by the king himself and later by his son, the future King Edward I. The barons sought to force the king to rule with a council of barons, rather than through his favourites. The war also involved a series of massacres of Jews by some of de Montfort's supporters in attacks aimed at seizing and destroying evidence of baronial debts. To bolster the initial success of his baronial regime, de Montfort sought to broaden the social foundations of parliament by extending the franchise to the commons for the first time. However, after a rule of just over a year, de Montfort was killed by forces loyal to the king at the Battle of Evesham.

Edward I, also known as Edward Longshanks and the Hammer of the Scots, was King of England from 1272 to 1307. Concurrently, he was Lord of Ireland, and from 1254 to 1306 ruled Gascony as Duke of Aquitaine in his capacity as a vassal of the French king. Before his accession to the throne, he was commonly referred to as the Lord Edward. The eldest son of Henry III, Edward was involved from an early age in the political intrigues of his father's reign. In 1259, he briefly sided with a baronial reform movement, supporting the Provisions of Oxford. After reconciling with his father, he remained loyal throughout the subsequent armed conflict, known as the Second Barons' War. After the Battle of Lewes, Edward was held hostage by the rebellious barons, but escaped after a few months and defeated the baronial leader Simon de Montfort at the Battle of Evesham in 1265. Within two years, the rebellion was extinguished and, with England pacified, Edward left to join the Ninth Crusade to the Holy Land in 1270. He was on his way home in 1272 when he was informed of his father's death. Making a slow return, he reached England in 1274 and was crowned at Westminster Abbey.

Simon de Montfort, 6th Earl of Leicester, 1st Earl of Chester, also known as Simon V de Montfort, was an English nobleman of French origin and a member of the English peerage, who led the baronial opposition to the rule of King Henry III of England, culminating in the Second Barons' War. Following his initial victories over royal forces, he became de facto ruler of the country, and played a major role in the constitutional development of England.