An archivist, historian specialising in Roman Gaul and renowned numismatist, Auguste Longnon joined the Commission de Topographie des Gaules (CTG) in its final years.
A noted autodidact
A shoemaker by training, Auguste Longnon became archivist at the Archives nationales in 1870, alongside which he completed historic works on Roman Gaul, topography, toponymy and philology. He then became a professor at the Collège de France and director of studies at the École pratique des hautes études. In 1897, he was appointed a member of the Académie des inscriptions et belles-lettres.
Passionate about historical geography
Auguste Longnon was introduced to scholarship by Alfred Maury and Anatole de Barthélemy. His major works were entirely in line with the work of the CTG: Géographie de la Gaule au VIe siècle (1878), Dictionnaire topographique de la Marne (1891), and above all his monumental Atlas historique de la France depuis César jusqu'à nos jours (1885).