Russian pioneer of the "haskalah" movement; died in Berdychev Jan. 6, 1886, at an advanced age. One of the first in Berdychev to become imbued with the spirit of progress, he sympathized with the efforts of the Russian government under Nicholas I. to spread secular knowledge among the Jews of Russia. When Lilienthal journeyed through Russia to induce the Jewish communities to establish schools, Rathaus acted as his secretary. In his later years, Rathaus, who was a man of wealth and a patron of Hebrew literature, was one of the prominent members of the Jewish community of Berdychev ("Keneset Yisrael," 1:1122).