ROSEN, MATHIAS (1804–1865), banker and member of the Polish Council of State. Rosen was born in Warsaw and took over his father's banking business there in 1846. Because of his financial status and close relations with the government, he was appointed head of the Warsaw community in the 1840s. In this capacity he established philanthropic institutions and fostered the influence of *Haskalah in religious education. As a result of the increase of the Jewish population in Warsaw, the leader of the community became the representative of all the Jews in the country. For his services, Rosen was elected a member of the Council of Warsaw in 1862, and in the following year of the Council of State. He was entrusted by Grand Duke Constantine with the commission to study the moral, industrial and agricultural conditions of the Alsatian Jews. Rosen collaborated with the Encyklopedja Powszechna of S. Orgelbrand and with the Biblioteka Warszawska, being a member of the editorial board from 1849.
Encyklopedja Powszechna, 22 (1866), 275; R. Mahler, Ha-Ḥasidut ve-ha-Haskalah (1961), 231–51; S. Lastik, Z. dziejów oświęcenia żydowskiego (1961), 186–243; J. Shatzky, Geshikhte fun Yidn in Varshe, 2–3 (1948–53), indexes. add. bibliography: M. Fuks, Zydzi w Warszawie (1992), index.