With Hitler's rise to power in 1933, Karlweis, who was of Jewish descent, returned to the Austrian stage; but with the Nazi Anschluss in 1938 he was again forced to flee, first to Switzerland and then Paris where, at both locations, he took to the stage with fellow Austrian law school dropout, writer/director, and cabaret performer Karl Farkas. When German forces took Paris in 1940, Karlweis, along with his friend Austrian writer Friedrich Torberg, fled via Spain to Portugal, whence they made their way to New York.