John de Warenne, 6th Earl of Surrey was a prominent English nobleman and military commander during the reigns of Henry III of England and Edward I of England. During the Second Barons' War he switched sides twice, ending up in support of the king, for whose capture he was present at Lewes in 1264. Warenne was later appointed as "warden of the kingdom and land of Scotland" and featured prominently in Edward I's wars in Scotland.

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 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 de Montfort's supporters, including his sons Henry and Simon, 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.