Why was the Battle of Lewes fought?

The Battle of Lewes (1264) was one of the key battle of the Second Baron’s War (the other being Evesham). It ended in a victory for the Baronial forces led by Simon de Monfort over the king, Henry III and his son the future monarch Edward I (he of Longshanks fame). The War itself arose out of the dissatisfaction of the Barons with Henry’s unpopular and autocratic rule. Henry was accused by the Barons of favouritism. They demanded Constitutional Reform in line with the Provisions of Oxford. Provisions of Oxford | English history

Henry sought to avoid these restrictions and allied himself with Louis IX of France. The two agreed on an annulment of the Provisions.

This set in motion the events of the Second Baron’s War that was punctuated initially by Baron success but ended in a Royalist victory, setting the stage for the strong military reputation of Edward I. On a very dark side the war itself was noted for the mass slaughter of Jews by Montfort’s supporters.

                                                                        Edward I