The four major German roles (Klink, Schultz, Burkhalter, and Hochstetter) and LeBeau were played by Jewish actors Werner Klemperer, John Banner, Leon Askin, Howard Caine, and Robert Clary. Caine was American-born-and-raised, the others fled the Nazis in the '30s and '40s. More details at http://en.wikipedia.org/wiki/Hogan%27s_Heroes