Kopust

The Kopust branch of the Chabad Hasidic movement was founded in 1866 by Rabbi Yehuda Leib Schneersohn after the death of the third rebbe of Chabad, Rabbi Menachem Mendel Schneersohn. The movement is named after the town Kopys in the Vitebsk Region of present-day Belarus, where Rabbi Yehuda Leib Schneersohn settled after his father's death.
The Kopust dynasty had four rebbes in total. Following the death of its last rebbe, the movement's membership dwindled and now has a few chasidim in Jerusalem and Chicago.
History.
Kopust is an offshoot of the Chabad-Lubavitch movement. The Chabad movement, founded by Shneur Zalman of Liadi, produced multiple offshoot groups through its over 200-year history. The death of the third Chabad rebbe Menachem Mendel Schneersohn led to a dispute over his succession leading to the founding of Kopust.
At the time of its founding, Kopust sought to be the rightful heir to the legacy of the first three rebbes of Chabad. Many of the greatest adherents of 19th-century Chabad were in fact Chassidim of Kopust.
Founding.
Rabbi Menachem Mendel Schneersohn, also known as the "Tzemach Tzedek", had seven sons. Following Rabbi Menachem Mendel's death in 1866, a dispute arose among several of his sons over the father's succession. While the youngest son, Rabbi Shmuel Schneersohn assumed the title of rebbe in the town of Lubavitch, another brother, Rabbi Yehuda Leib Schneersohn, assumed the title of rebbe in the town of Kopys in Belarus. Rabbi Yehuda Leib died less than a year later and was succeeded by his son Rabbi Shlomo Zalman Schneersohn.
Leadership.
The Kopust movement had four rebbes:
Kopust today.
It is thought that after the death of the fourth rebbe of Kopust, the adherents of the Kopuster movement rejoined the Chabad-Lubavitch movement.
The oldest extant Chabad synagogue in Israel, the "Ohel Yitzchok" (אהל יצחק) synagogue in the Mea Shearim neighborhood of Jerusalem—also called the "Baal HaTanya Shul" (: "Baal HaTanya's synagogue")—active since 1900, was originally affiliated with Kopust. When the Lubavitcher Rebbe Yosef Yitzchak Schneersohn visited Jerusalem in 1929, he did not visit this synagogue.
Relationship with Chabad-Lubavitch.
While the Kopust movement originally was at odds with the Chabad-Lubavitch movement over the successor to the third Chabad rebbe, the sixth Lubavitcher Rebbe, Rabbi Yosef Yitzchak Schneersohn referred to the Rebbes of Kopust as "Admorim", or rebbes. This may be seen as a sign of respect to the Kopust dynasty.