St. Louis de Montfort was a French priest and missionary born in 1673. He is best known for his devotion to the Virgin Mary and his teachings on the importance of Marian devotion in the spiritual life. He founded the Company of Mary and the Daughters of Wisdom, which focused on education and spiritual growth. De Montfort wrote several influential works, including "True Devotion to Mary," which emphasizes total consecration to Jesus through Mary. He was canonized as a saint in 1947 and is recognized as a significant figure in the Catholic Church, particularly for his contributions to Marian spirituality.