Founded in 1918, by Léonce Rosenberg (1877-1947), the gallery served as a major promoter of avant-garde art, in France and Europe, as a whole, during the 1920s.
Léonce Rosenberg, along with his brother, Paul Posenberg (1881-1959), initially started their careers as dealers of OLD MASTERS, IMPRESSIONIST and POST-IMPRESSIONIST art. In 1910, after splitting their business, Léonce became a leading promoter of CUBISM, and began working with artists such as BRAQUE, GRIS and LÉGER.
The Gallery also published the BULLETIN DE L`EFFORT MODERNE, between 1924 and 1927.