 Throughout the Middle Ages (5th to 15th centuries) the site of Penne was of military strategic importance, being situated on the borders of the provinces of Albigeois, Quercy and Rouergue, with its fortress perched atop a cliff overlooking the River Aveyron.As such, it was frequently the target of attack, most notably during the Albigensian Crusade - a twenty-year military campaign (1209-1229) initiated by the French king, Phillip II and the Roman Catholic pope, Innocent III.Ostensibly, the objective of the crusade was the elimination of all Cathars in southern France, but this coincided with the French king's political ambition to annex the area to his northern territory.