Yaakov Yisrael Kanievsky

(Hebrew: יעקב ישראל קַנִיֶּבְסְקִי), known as The Steipler or The Steipler Gaon (1899 – 10 August 1985),^[2][3] was a Haredi rabbi, Talmudic scholar, and posek^[4] ("decisor" of Jewish law), and the author of Kehilos Yaakov, "a multi-volume^[5] Talmudic commentary". ^[6]

The Steipler was born in Hornostaypil, Ukraine to Rabbi Chaim Peretz Kanievsky, a Chernobyl Chassid and the local shochet, and the latter's second wife Bracha.^[a] It was the family's subsequent move to the town of Hornostaypil, from which his appellation, "the Steipler", was later derived.^[8]

Around the age of 11,^[3] Kanievsky entered the Novardok Yeshiva in Navahrudak, studying under its famed rosh yeshiva, Rabbi Yosef Yoizel Horowitz. By age 19, having progressed rapidly and gained a reputation as a talmid chacham, he was recommended by Rabbi Horowitz "to head a yeshiva in Rogatshov"^[3] – as a branch of Horowitz's yeshiva.