R. Unterman (1886 - 1976), Ashkenazi chief rabbi of Israel, was born in Brest-Litovsk, Belorussia, he studied at the Maltash, Mir, and Volozhin yeshivot and was ordained by R. Raphael Shapiro. At the age of 24 he was appointed rosh yeshivah in Vishova, Lithuania, and served subsequently as rabbi of various Lithuanian communities. His last position there was as rabbi of Grodno during 1921–24. Possessing oratorical and expository talents of a high order, he attained a distinguished record during World War I as a communal leader after representing the community before the authorities, and in the postwar period he displayed outstanding organizational gifts in the reconstruction of the Lithuanian yeshivot. In 1924 he was appointed rabbi of Liverpool, England, and, rapidly mastering English, soon made his influence felt. A fervent Zionist, he became president of the British Mizrachi Organization and appeared before the Anglo-American Inquiry Commission on Palestine in 1946. He championed the rights of aliens and was a member of the Council of Christians and Jews.
In 1946 Rabbi Unterman was elected Ashkenazi chief rabbi of Tel Aviv-Jaffa in succession to Rabbi M. A. Amiel, and in 1964, Ashkenazi chief rabbi of Israel, succeeding Rabbi I. Herzog. During his period of office in Tel Aviv he organized the rabbinic courts, making them a model of efficiency. He founded two kolelim (graduate talmudical academies) - Shevet mi-Yhudah in Tel Aviv and Shevet u-MeHokekim in Jerusalem - where he introduced a systematic method of Talmud study based on the practical halakhah for select students preparing for the rabbinate and for service as religious functionaries and teachers in advanced yeshivot. While he insisted on unflinching loyalty to the minutiae of the halakhah, he approached public issues with moderation and understanding. In 1952 he toured the U.S. on behalf of the United Jewish Appeal and helped to strengthen the relationship between the American and Israel rabbinates. Rabbi Unterman wrote Shevet mi-Yhudah (1952), on problems of halakhah. He contributed to many rabbinical periodicals and made valuable additions to the Ozar ha-Posekim, the digest of responsa literature. Many of his responsa appear in the works of others and are a model of lucidity.
His Ner ha-Ma'arav (1911), the history of the Jews in Morocco from the commencement of their settlement and the biographies of its great rabbis, is a basic work for research into the origins of Jewry in North Africa. His other books included Appiryon (Jerusalem, 1905), a bibliography of the supercommentators to Rashi's commentary to the Pentateuch; Yedei Moshe (Safed, 1915), a commentary on the Mishnah Pesahim by Maimonides from a manuscript; Yam ha-Gadol (Cairo, 1931), responsa; Sarid u-Falit (Tel Aviv, 1945), giving passages from manuscripts on ancient works dealing with the Talmud, Jewish scholarship, the history of the settlement in Erez Israel, and bibliography; and Ozar Genazim (1960), a collection of letters on the history of Erez Israel from ancient manuscripts, with introductions and notes.