Louis de Cazenave was born and raised in Saint-Georges-d'Aurac in the Auvergne region of south central France. When he turned nineteen years old, at the end of 1916, he was mobilized into the military. He found himself in various units before being assigned to the colonial infantry front in the 5th Senegalese Tirailleur Battalion and fought in the Battle of Chemin des Dames.