Born in Paris, Louis J. Gasnier began his career in the theatre as an actor and director. Accounts vary as to when his film career began; according to Gasnier himself, his association with Pathé Frères commenced in 1899, during the earliest days of the company. Georges Sadoul recognized Gasnier as a member of early French filmmakers known as the 'Vincennes School' which also included Gaston Velle, Georges Hatot, Lucien Nonguet, Lépine, Andre Heuré, Georges Monca, and Albert Capellani. However, Pathé was notoriously stingy with credits in those days, so no credits for Gasnier are known before 1905.