Charles Tournemire (Bordeaux, January 22, 1870 – Arcachon, November 3, 1939), was a French composer and organist, most famous for his improvisations. While he could play the conventional organ literature expertly, he rarely played anything in his titular post other than his own improvised works. His improvisations were consistently brilliant, and most often rooted in Gregorian thematic material. His output contains many organ works, including a cycle L'Orgue Mystique of pieces for the entire liturgical year