R. Benzion Eisenstadt (1873–1951), was born in Kletsk, Belorussia. In his youth he was attracted to modern Hebrew literature and while in his teens corresponded with Jewish scholars, such as Slonimski and Buber. While still in Russia he published Zioni (Warsaw, 1895; Parts 2–4, Vilna 1899–1902), a biographical dictionary of contemporary rabbis and scholars, and Rabbanei Minsk va-Hakhameha, on the rabbis and scholars of Minsk (Vilna, 1899), as well as Ve-Zot li-Yehudah (1901), annotations on Noda bi-Yehudah, the responsa of R. Ezekiel Landau.

In 1903 he emigrated to the U.S. where, in addition to talmudic works, he continued to publish biographical works on well-known rabbis, scholars and communal leaders. They include Hakhmei Yisrael be-Amerikah (with photographs, 1903), Dorot ha-Aharonim (2 vols., 1913, 1917), Anshei ha-Shem Be-Arzot ha-Brit (1933) and, posthumously Benei Hiyyon (1952).