Karl Isaac was born in Cologne in 1889. He studied medicine in Göttingen, Berlin, Heidelberg, Munich and Bonn. In 1914 he married Auguste Krieger of Karlsruhe and in 1920 they formally changed their surname to Isaac-Krieger. During WWI he fought in France and served as a field doctor. Following the war he worked at the Rudolf Virchov Hospital in Berlin and later gave classes in diet-cooking at the Lettehaus, in addition to running a private practice. In 1938 he emigrated with his wife and daughter, Eva, to the United States where he quickly received his license to practice medicine and eventually was employed at the Lenox Hill and Beth Israel hospitals in New York. He was a member of numerous professional medical associations and frequently published articles on gastroenterology. He died in 1969 in New York.
From the guide to the Karl Isaac-Krieger Collection., 1846-1969, (Leo Baeck Institute Archives)
