Louis IX, also known as Saint Louis, was a King of France from 1226 to 1270. He is known for his piety, justice, and commitment to the welfare of his people. Louis IX was a devout Christian and was canonized as a saint after his death. He is also remembered for his efforts to promote justice and fairness in his kingdom, as well as for his participation in the Crusades. Louis IX is considered one of the most respected and admired kings in French history.