Rabbi Yosef Yitzchak Schneerson, also known as "Der Frierdiker Rebbe" (The Earlier Rebbe) to distinguish him from his successor, Rabbi Menachem Mendel Schneerson, was the sixth leader of the Chabad-Lubavitch movement. Living in tumultuous times, he shifted the center of the movement from its Eastern European origins to its current headquarters in the United States. Part of the Jewish Biography as History Series, more available at www.henryabramson.com.