In Shakespeare's Henry IV, Part 1, Henry "Hotspur" Percy recalls the valour of Edmund Mortimer, 5th Earl of March in a long battle against Welshman Owain Glyndŵr upon the banks of the Severn, claiming the flooding Severn "affrighted with [the warriors'] bloody looks ran fearfully among the trembling reeds and hid his crisp head in the hollow bank, bloodstained with these valiant combatants."
