Louis de Cazenave was, at the time of his death, the oldest French poilu still alive. As of December 11, 2007, he was the fourth-oldest man in Europe and the eleventh-oldest man in the world as well, until his own death just 40 days later.
Born and raised in Saint-Georges-d'Aurac and mobilized at the end of 1916, he found himself on the colonial infantry front in the 5th Senegalese Tirailleur Battalion, and he took part in the battle of Chemin des Dames.
At the end of the war, de Cazenave returned to Haute-Loire and married in 1920 to Marie, a postmistress with whom he had three sons. He became a railwayman, joining the predecessor to the SNCF. His experiences led him to become a convinced pacifist; later on, he participated in the strikes and demonstrations of the Popular Front in 1936 before going into retirement in 1941. During the Nazi occupation of France, he subscribed to the banned left-wing libertarian journal La Patrie Humaine and was imprisoned by the pro-Nazi regime.
He lived in Brioude with his family. Although at first refusing any decorations, de Cazenave accepted the Légion d’honneur in 1995, along with several other veterans.