Sabbatai Zevi
Critics of Hasidic Judaism expressed concern that Hasidism might become a messianic sect as had occurred among the followers of both Sabbatai Zevi and Jacob Frank. However the Baal Shem Tov, the founder of Hasidism, came at a time when the Jewish masses of Eastern Europe were reeling in bewilderment and disappointment engendered by the two Jewish false messiahs Sabbatai Zevi (1626–1676) and Jacob Frank (1726–1791) in particular.