The eldest son of Rabbi Shneur Zalman of Liady, who was the founder of Chabad Chassidism and had suffered the full force of the anti-Chassidic backlash, Reb Dov Baer became the leader of the Chabad dynasty after his father's death in 1813. He moved the group to the town of Lubavitch in Russia, after which the group became known. As a prolific writer, he expanded on the mystical works of his father, and helped to further differentiate the Chabad movement from other forms of Chassidism. Like his father, Reb Dov Baer was imprisoned by the Russian authorities after allegations by opponents, but was released soon after.
Sources: Orthodox Union