Hans Janowitz (1890-1954) was a friend of Franz Werfel's since their school days in Prague; he was the older brother of the poet Franz Janowitz (also a friend of Werfel's; 1892-1917) who was killed in World War I. Hans Janowitz was a prose and screenplay writer (co-writer with Carl Mayer of the script for "Das Cabinet des Doktor Caligari"); he emigrated to the U.S. in 1939. He was a member of the Executive Committee of the European Friends of HIAS; the latter organization, founded in 1943 as part of the Hebrew Sheltering and Immigrant Aid Society of America (also known as HIAS), was dedicated in particular to the aid of Jews in Europe.
From the description of Correspondence with Alma Mahler and Franz Werfel, 1944-1945. (University of Pennsylvania Library). WorldCat record id: 155863557