In the history of the cinema, the German director Veit Harlan occupies an especially ignominious position. It is his name that is attached to “Jew Süss,” perhaps the most notoriously anti-Semitic movie ever made, a box office success in Nazi Germany in 1940 that was so effective that it was made required viewing for all members of the SS. But what motivated Harlan to write and direct such a film? Was he a Nazi true believer, an opportunistic careerist or just a filmmaker too fearful of retribution to say no to Joseph Goebbels, the Nazi propaganda chief? Those are some...