Charles Cometti was not quite 17, when he worked for a woodcutter – who brought him into contact with the antifascist French resistance movement. Cometti joined it, and took the name "Charlemagne" – which would stick with him for the remainder of his long life. His group achieved several acts of sabotage against the Nazis and their French Vichy vassals in the area of Mirebeau-sur-Bèze (Burgundy), particularly obstructing train transports; Charlemagne was a machine gunner for the resistance fighters.
From 1944, his group operated from a farm called Leuzeu where they had settled. One of the resistance members deserted, and led the Vichy militia to the farm on July 30th, 1944: 400 militiamen against 80 antifascists, Cometti among them. And the resistance fighters won the battle! One of the great feats of the French resistance movement.
After the war, Cometti became an opera tenor and started his career in Dijon. Later on, he was a member of the Algiers opera, and still later, in January 1966, I find him in Limoges in operetta (La mascotte, more precisely).
His career doesn't seem to have lasted very long; when he gave it up, he became a restorer.
He grew very old, but still, on every patriotic occasion, he would gladly contribute a heartfelt rendition of the Marseillaise. When in 2018 a group of police cadets decided to restore what was left of the Leuzeu farm as a memorial, Cometti was the only Leuzeu hero still alive, and ran up the French flag at the project's inauguration ceremony; and of course, sang the Marseillaise along with the cadets. Two months later, Cometti was dead.
Reference 1 and picture source (age 91): L'Essor de la Gendarmerie, 10 September 2018; reference 2: DijonMag, January 2019; reference 3