By the late 13th century, Tenby castle and the town had become part of the Marcher Lordship of Pembroke, which by then was ruled by William de Valence, 1st Earl of Pembroke.[1]. The French knight, who was married to the Joan de Munchensi, the granddaughter and heir of the previous Earl of Pembroke, had provided military service to Henry III in the Second Barons' War. He instigated the building of stone walls around the town.