Canonized in 1297 as Saint Louis, King Louis IX of France (1214-1270) was the central figure of Christendom in the thirteenth century. He ruled when France was at the height of power; he commanded the largest army in Europe and controlled the wealthiest kingdom. Renowned for his patronage of the arts, Louis was equally famous for his choice to imitate the suffering Christ as a humbly attired, bearded penitent. Armed with the considerable...