1919 French and British scientists seek to exclude German scientists from international meetings. Albert Einstein -- a Jew traveling with a Swiss passport -- remains an acceptable German envoy. His political views as a pacifist and a Zionist pitted him against conservatives in Germany, who had branded him a traitor and a defeatist. The public success accorded his theories of relativity evoked savage attacks during the 1920s by anti-Semitic physicists such as Johannes Stark and Philipp Lenard.