The last crusader king, Louis IX of France, did not die of scurvy. He died of dysentery during the Eighth Crusade in 1270. Scurvy is a disease caused by a deficiency of vitamin C, which is found in fresh fruits and vegetables. During the Middle Ages, scurvy was a common problem for sailors and soldiers who were away from fresh food for long periods of time. However, Louis IX's army was well-supplied with fresh food, so it is unlikely that he died of scurvy.