Discusses social and political conditions bearing on antisemitism and philosemitism in France, Russia, and the American South as background for the Dreyfus Affair, the Beilis ritual murder trial, and the trial and lynching of Leo Frank. Declares that comparison helps to understand each of these affairs. Antisemitism is based on realities enhanced by fantasy: in the 19th century it increased because of the growth in the number and influence of Jews, as well as domestic and international political conditions. In all three trials, official antisemitism played little part either in directing suspicion at the particular defendants or in the prosecution: in all three, there was circumstantial evidence that at first seemed credible. Public debate, however, turned on antisemitism and philosemitism. also describes massive Jewish defense efforts, especially in the USA, in connection with all three trials.