I Rebbe Rashab: Rabbi Sholom DovBer Schneersohn also known as "the Rebbe Nishmosei Eiden (1860–1920) fifth Lubavitch Rebbe 1893-1920. second son of the fourth Chabad Rebbe the Rebbe Maharash. Born in Lubavitch, Russia, interred in Rostov, Russia. Founded the flagship Chabad Yeshivah Tomchei Temimim. Known informally as "Rambam of Chabad Chassidus" (from his encyclopaedic work on developing Chabad Chassidic philosophy into an organized system), Rebbe Rashab was a prolific writer on Chabad theology. His written works provide the first systematic organization of Chabad thought and provide the basis of these studies in Chabad Yeshivahs today. Much of his work has been published in Hebrew, and some of it has been translated into English, and is available online. Sefer HaMaamorim - Igros Kodesh - Toras Sholom. Kuntres Uma'ayan. Kuntres HaTefillah. Kuntres HoAvodah. Maamar Heichaltzu. Kuntres Eitz HaChayim. Chanoch Lana'ar. The Rebbe Rashab delivered a series of Chassidic discourses that came under the heading ‘Hemshech Ayin Beis 5672’ starting in the year 5672 (1911-12). This series of Chassidic essays are considered a fundamental work of Chabad mysticism for its original treatment of many Chassidic concepts. The Ayin Beis series is the longest series of Maamorim from any Chabad Rebbe. This series was written and delivered over the course of several years. In its final form, the series consists of 144 discourses, a number of which were never delivered publicly. The work is also referred to as Hemshech Tehrav from the letters of the number of the year in which it was started. The importance of toiling in one’s study is explained at length over there. His teachings also represent the emergence of an emphasis on outreach that later Chabad Rebbes developed into a major theme.
II Rashi: Rabbi Shlomo Yitzchaki, Troyes, France 1040-1105, author of the commentary on the Talmud and Tanach, virtually all published copies of the Chumash and of Talmud include Rashi’s commentary.
III Akeida: or Akeidas Yitzchok Reb Yitzchok ben Moshe Arama (c. 1420 – 1494) was a Spanish rabbi and author. Zamora, Tarragona, Fraga in Aragon, and Calatayud. Upon the expulsion of the Jews in 1492, Arama settled in Naples, where he died in 1494. Also authored Chazus Koshoh .Yad Avsholom.
IV Frierdiker Rebbe: The Rebbe Rayatz, Rabbi Yosef Yitzchak Schneersohn, sixth Rebbe of the Chabad Lubavitch Chassidic movement. (born: 1880, in Lubavitch, Russia, returned his soul: 1950). Father-in-law of the Rebbe. Son of the fifth Lubavitcher Rebbe, the Rebbe Rashab. Some of his works include: Sefer Hamaamarim, Sefer Hasichot, Likkutei Dibburim, Kuntres Toras Hachasidus, Kuntres Limud Hachasidus, Admur Hatzemach Tzedek U’Tenuas Hahaskalah, Kitzurim L’Biurei Hazohar, Sefer Hakitzurim – Shaarei Orah, Kitzurim L’Kuntres Hatefillah, Sefer Hazichronot, Moreh Shiur B’Limudei Yom Yom (Chumash, Tehillim, Tanya) Seder Haselichos, Maamar V’Ha’ish Moshe Onav 5698, Igros Kodesh, Klalei Chinuch veHaDracha. But mostly famous for his steadfastness for Yiddishkeit specifically in the former USSR and his willingness to show self-sacrifice for that cause. Famous statement: “America Is Nisht Andersh” implying that the same Torah values fought for in eastern Europe were still just as important in the free world.
V Alter Rebbe: Rabbi Shneur Zalman of Liadi, founder and first Rebbe of Chabad, 1745-1813. Author of Shulchan Oruch HoRav, and the Tanya. Delivered Maamorim that were then published in Likkutei Torah, Torah Or and Maamorei Admur Hazoken.