Rabbi Yissocher Dov Illowy

A communal rabbi and Orthodox polemicist in 19th‑century Europe and the United States, Rabbi Yissachar Dov (Bernard) Illowy combined traditional semikhah from the Chasam Sofer with a PhD from the University of Budapest. After immigrating to America, he served in a succession of pulpits in major cities while publishing halachic and polemical writings defending traditional Torah observance against Reform innovations. His collected sermons and letters, including his responsum on the kashrus of the Muscovy duck, were later gathered in the volume Sefer Milchamos Hashem (Letters of the Orthodox Rabbis of America to Their Colleagues in Germany).