Oscar Marin was born in Charleroi, the ‘black country’ or coal-mining & steel smelting region of Belgium, about 30 miles south of Brussels. He was trained by Leon Van den Houten (1874-1944), who was a painter, designer, sculptor and ceramicist, and who taught the decorative arts at the Paul Pasteur Institute in Charleroi and drawing in the local art school. Van den Houten was naturally drawn to Impressionism, but also to the major avant garde movements. He was involved with L’Essor, La Libre Esthetique, and helped to found the Groupe Art Libre. His eclecticism influenced his students, and notably Marin, in whose work can be seen echoes of painters from Cézanne and Picasso to Bonnard and Delvaux.
Marin was friendly with another of Van den Houten’s students, Gustave Camus, who in 1933 founded (with the sculptor, Georges Wasterlain) an avant garde group, L’Art Vivant au Pays de Charleroi, which included Marin. In 1937 Camus and Marin travelled to Holland and discovered Rembrandt together. Marin exhibited at the Salon of Ghent.