Little is known about Deutsch's life. He was a perfectionist and a discreet man who did not often appear in public. He had a close friendship with Rudolf Ernst, with whom he shared his passion for Orientalist painting. He settled in Paris and eventually became a French citizen. Deutsch painted scenes of ordinary and religious life, demonstrating tremendous skills in his representations of human expressions and gestures, the subtleties of clothing, and the beauty of Islamic architecture and decoration. He also used professional photographs of settings as a basis for his artwork. His compositions appear natural and at the same time sophisticated, with an exotic and romantic touch.