Son of Alexis Mossa, artist and French and “Nissard” writer, he studied at the National School of Decorative Arts of Nice (1897-1898). Together with his father, he painted a large number of landscapes of Nice, at the same time he began to write fanciful comedies. From 1904 and for about fifteen years, he has been a brilliant representative of symbolism : pictorial realizations, essentially watercolours, which translated a personal crisis through a striking reinterpretation of ancient myths or of biblical episodes. The same aesthetics to serve the same theme (femme fatale, war of the sexes, " dismal Eros ", artists victims of a materialist and unsympathetic society), the same figures (Salomé, Pierrot...) expressed itself in numerous literary essays, essentially dramatic essays, all remained unpublished. He began his period of creative activity in Nice and pursued it in the Paris region with Charlotte-Andrée Naudin, whom he married in 1908. He intended to adapt for the theater simultaneously famous texts (Gulliver, the Divine comedy, etc.) and painters' lives (Lucas de Leyde, in 1903, Goya, Watteau, Botticelli, in 1914, etc.). Having discovered in Brugge in 1911 Gothic art and the sacred paintings of the Flemish Masters, he evolved towards the art of the former "painters of popular pictures”. His meeting with the poet René d' Helbingue ( 1882-1969 ), who will be a faithful friend, the cruel experience of war (he was injured in Ypres in November, 1914), the progressive disappearance of his neurosis, the breaking off with his first wife and his remarriage ( 1918 ) were so many steps on the way to his spectacular transformation. He has drawn models of carnival floats since 1902 and will continue till his death. On the literary ground, he returned to the fanciful inspiration of his youth,he was interested in Rabelais, in La Fontaine, in Boccace, he returned to optimism and rediscovered the popular and regional culture which ended in the writing, in association with his friend Barthélemy Marengo, of a pastoral in “nissart” language, Lou Nouvé o sia lou pantai de Barb' Anto ( 1922 ). This play gave the signal of the renewal of the dialectal theater. The success encouraged him to adapt for the theater Nemaïda de Rancher ( 1923 ), then to create and manage Lou Teatre de Barba Martin. Until 1940, the company will play his dialectal comedies (Phygaço, in 1924, La Tina, in 1926, L’Anticari, in 1933, Lou Rei Carneval, in 1935) which were characterized by their humor, their dramaturgic qualities and the richness of their traditional themes. Barba Martin also created plays written by F. Gag (Lou Sartre Matafiéu, in 1932), by G. Boréa (L’Esprit foulatoun, 1933, etc.), by G. Delrieu (Fai calà, in 1934, Li Fachenda de Picalé, in 1936, etc.) including shows of traditional or modern songs (L. Genari and G. Delrieu). Mossa, who became curator of the Museum of Fine art of Nice in 1927, led from 1913 till 1940 a career of illustrator of books and luxury reviews of international reputation. From the Second World war till his death, he dedicated himself especially to his " painter of popular pictures "’ works on the City of Nice, illustrating official documents, drawing armorial bearings and traditional suits of the County, but never interrupted his plentiful production of figurative watercolours dedicated to the landscapes of the region. In the pictorial domain, Mossa brought to the finishing symbolism an exceptional contribution; on the dramatic ground, he was one of the striking personalities of the theater of Oc in the interwar period.
Fournet Claude et Soubiran Jean-Roger : Gustav Adolf Mossa et les symboles. 1883-1971. Exposition, Nice, Direction des Musées de Nice, 1978
Soubiran Jean-Roger : G.-A. Mossa, Nice, Ediriviéra-Alligator, 1985
Lafon Sylvie et Clais Anne-Marie : Gustav Adolf Mossa, la scène symboliste, Nice, Z'éditions, 1993
Nice Historique, n° spécial « Gustave Adolphe Mossa illustrateur », 1996, n° 3-4, pp. 129-216
Gasiglia Rémy : Le Théâtre nissart aux XIXe et XXe siècles. Etude historique, dramaturgique et thématique d'un phénomène culturel de langue d'oc, thèse d'Etat, Université de Nice, 1994, 5 tomes, passim.