At the start of the war, in September 1914, De Scévola, serving as a second-class gunner, experimentally camouflaged a gun emplacement with a painted canvas screen. On 12 February 1915 General Joffre established the "Section de Camouflage" () at Amiens. By May 1915 the Section de Camouflage put up its first observation tree, an iron lookout post camouflaged with bark and other materials during the Battle of Artois. By the end of 1915, De Scévola became commander of the French Camouflage Corps, employing cubist artists such as André Mare, a specialist in camouflaging lookout posts. By 1917, De Scévola's team had grown to 3000, taking in artists including Jacques Villon, André Dunoyer de Segonzac, Charles Camoin, Louis Abel-Truchet and Charles Dufresne.