Louis Lewin (1868-1941) was born in Znin, Posen, but was raised in Frankfurt am Main. He earned a Ph.D. degree at the University of Heidelberg in 1893 for his dissertation on Rabbi Simeon bar Yohai, and obtained rabbinic ordination at the Hildesheimer Seminary in Berlin. While in Berlin he also studied with Moritz Steinschneider, the noted Judaica bibliographer, at the Veitel-Heine Ephraim'sche Lehranstalt. Lewin followed in his mentor Steinschneider’s footsteps and developed a keen interest in collecting books and manuscripts.