King Louis IX of France passes judgement when the Abbot of Saint Nicholas-au-Bois accuses a knight (Enguerrand De Coucy) of wrongly hanging three young men. From a French illustration of 1330. Louis IX (April 25, 1214 - August 25, 1270), commonly Saint Louis, was King of France from 1226 until his death. He is the only canonized king of France. Louis went on two crusades, in his mid-30s in 1248 (Seventh Crusade) and then again in his mid-50s in 1270 (Eighth Crusade). His patronage of the arts drove much innovation in Gothic art and architecture, and the style of his court radiated throughout Europe by both the purchase of art objects from Parisian masters for export and by the marriage of the king's daughters and female relatives to foreign husbands and their subsequent introduction of Parisian models elsewhere. He was a devout Catholic, and he built the Sainte-Chapelle (Holy Chapel), located within the royal palace. Louis died at Tunis in 1270 during his second crusade. He was traditionally believed to have died from the bubonic plague but the cause is thought by modern scholars to have been dysentery.