Louis-Denis Chalain, born January 10, 1845, at Le Plessis-Dorin (Loir-et-Cher) and died October 14, 1895, in Paris, was a socialist militant and member of the Paris Commune. This albumen-print carte de visite is a bust-length portrait produced by the Nadar studio at 51, rue d'Anjou Saint-Honoré, Paris, dateable to the early 1870s on the basis of the studio address and the subject's known chronology. Nadar, the pseudonym of Gaspard-Félix Tournachon (1820–1910), was one of the foremost portrait photographers of nineteenth-century Paris, and his studio produced CDVs of many prominent political and cultural figures of the period.

The subject faces the camera in a three-quarter pose with a direct, composed expression. He wears a dark double-breasted coat over a white shirt, finished with a large loosely knotted silk cravat at the throat. His hair is full, curly, and worn long to the sides, and he carries a thick beard and mustache. The plain neutral-tone studio backdrop keeps the emphasis entirely on the face and figure.

A bronze-turner by trade and a member of the International Workingmen's Association, Chalain was elected to the Council of the Commune by the 17th arrondissement and served on the Commission of General Security and the Commission of Labor and Exchange. After the Bloody Week, he was condemned to death in absentia and took refuge in London, then Austria, and finally Switzerland, where he continued to organize within socialist movements.

The recto mount bears the Nadar signature in red ink at lower left and the handwritten inscription "Clovis Hugues" (the name of a contemporary French politician, written in ink, likely by a prior owner in error) alongside the printed studio address. The reverse bears pencil inscriptions reading "Chalain" and "Louis-Denis Chalain / Communard," along with an oval dealer's stamp reading "J. H. Lang, Bale (Suisse) / Succr de Rod. Lang," and the notations "7/21/11," "OFEDCZ," and "Eb" in pencil at the lower edge.