Neumann began his career in 1913 designing commercial posters as well as graphic inserts for magazines, flyers, brochures, and even sheet music. Prior to World War I, he worked briefly in Berlin while growing his business back in Austria. Among his largest clients were Mercedes-Benz, Persil, and Krupnik's Moden. As it became more and more obvious that Europe was heading towards war, he fled Austria in 1938, first to London, and then settling in Sydney, Australia where he continued to work in graphic design.