 In December 1264 he was given a safe conduct to visit the king, and then in May 1265 he spoke with Edward, helping organise his escape from Kenilworth Castle on 28 May.Leybourne subsequently fought at the Battle of Evesham, reportedly saving the king's life, and for the two years of conflict after Evesham served as Edward's principal lieutenant.In August 1265 he was made keeper of Westmorland, in October he was given custody of Carlisle Castle, made High Sheriff of Cumberland and trusted with subduing London on behalf of the king.