Gentleman's Agreement is a 1947 novel by Laura Z. Hobson which explored the problem of antisemitism in the United States, what The New York Times called, in a contemporary review, "a story of the emotional disturbance that occurs within a man who elects, for the sake of getting a magazine article, to tell people that he is a Jew and who experiences first-hand, as a consequence, the shock and pain of discriminations and social snubs." No. 1 on The New York Times Fiction best seller list for 4 weeks, from the issue of July 20, 1947. Wiki link