Saint Louis. Louis IX, commonly known as Saint Louis, is the only King of France to be canonized in the Catholic Church.
Louis was crowned in Reims at the age of 12, following the death of his father Louis VIII; his mother, Blanche of Castile, ruled the kingdom as regent until he reached maturity. During Louis' childhood, Blanche dealt with the opposition of rebellious vassals and obtained a definitive victory in the Albigensian Crusade which had started 20 years earlier.
As an adult, Louis IX faced recurring conflicts with some of the most-powerful nobles, such as Hugh X of Lusignan and Peter of Dreux. Simultaneously, Henry III of England tried to restore his continental possessions, but was utterly defeated at the battle of Taillebourg.
His reign saw the annexation of several provinces, notably parts of Aquitaine, Maine and Provence. Louis IX was a reformer and developed French royal justice, in which the king was the supreme judge to whom anyone could appeal to seek the amendment of a judgment.
He banned trials by ordeal, tried to prevent the private wars that were plaguing the country, and introduced the presumption of innocence in criminal procedure. To enforce the application of this new legal system, Louis IX created provosts and bailiffs. Following a vow he made after a serious illness and confirmed after a miraculous cure, Louis IX took an active part in the Seventh and Eighth Crus