Khorloogiin Choibalsan (8 February 1895 – 26 January 1952) was a Mongolian politician who served as the leader of the Mongolian People's Republic as chairman of the Council of Ministers (premier) from 1939 until his death in 1952. He was also commander-in-chief of the Mongolian People's Army from 1937, and chairman of the Presidium of the State Little Khural (head of state) from 1929 to 1930. A close ally of Joseph Stalin, Choibalsan led a dictatorship and organized Stalinist purges in Mongolia between 1937 and 1939 as head of the Ministry of Internal Affairs, executing tens of thousands of Mongolian citizens.

Choibalsan was one of the 1921 Mongolian revolutionaries, and held several political and military roles in the 1920s. His rise to power in the 1930s was personally orchestrated by Stalin, and his rule was maintained by a repressive state and cult of personality. Mongolia's economic, political, and military ties to the Soviet Union deepened, though after World War II, Choibalsan supported pan-Mongolian unification with Inner Mongolia. He died of cancer in Moscow in 1952, and was succeeded as leader by his protégé, Yumjaagiin Tsedenbal.

Early life
Choibalsan was born on 8 February 1895 in Achit Beysiyn, near present-day Choibalsan, Dornod Province. He was the youngest of four children born to a poor unmarried herdswoman named Khorloo (the name Khorloogiin is a matronymic). His father was likely a Barga tribes man, Daur Mongol from Inner Mongolia called Jamsu, but Choibalsan claimed to be unaware of his identity. Named Dugar at birth, he assumed the religious name Choibalsan at age 13 after entering the local Buddhist monastery of San Beysiyn Khüree where he trained to be a Lamaist monk. Five years later he fled to Khüree (also known as Urga—present-day Ulaanbaatar) with another novice where he worked odd jobs. In part to prevent him from being returned to the monastery, a sympathetic Buryat teacher named Nikolai Danchinov had him enrolled in the Russian consulate's Russian-Mongolian Translators' School. A year later he was sent on at public expense to study at a gymnasium in Irkutsk, Russia from 1914 to 1917.

Mongolian Revolution of 1921

Formation of the Mongolian People's Party

Choibalsan and fellow Mongolian students in Russia were called back to Khüree by the Bogd Khaan government following the 1917 October Revolution. Exposed to Bolshevism while living among Irkutsk's radicalized student population, Choibalsan joined the revolutionary Consular Hill or Konsulyn Denj (Консулын дэнж) group, heavily influenced by Bolshevist philosophy and established to resist the Chinese occupation of Outer Mongolia after 1919. Original members of the group also included Dambyn Chagdarjav and Darizavyn Losol. Dogsomyn Bodoo, the group's leader, was a former teacher and mentor of Choibalsan's at the Russian-Mongolian School for Translators. With his serviceable Russian, Choibalsan served as the group's translator with contacts at the Russian Consulate. Those contacts later encouraged Konsulyn Denj to join forces with the more nationalist-oriented resistance group Züün Khüree (East Khüree), which counted Soliin Danzan, Dansrabilegiin Dogsom, and Damdin Sükhbaatar among its members. On 25 June 1920, the new body adopted the name Mongolian People's Party (MPP). In 1924 the party renamed itself the Mongolian People's Revolutionary Party or MPRP after the death of the Bogd Khaan and the formal proclamation of the Mongolian People's Republic (MPR).

Contact with Soviets and the first MPP Congress
In late June 1920, Choibalsan and Danzan embarked for Irkutsk (they were later joined by Losol, Chagdarjav, Dogsom, L. Dendev, and Sükhbaatar—the famous "First Seven") to establish contacts with the Soviets and seek assistance in their struggle for independence. Choibalsan and Sükhbaatar remained together in Irkutsk for several months raising awareness of Mongolia's plight and receiving military training. During this period Sükhbaatar gradually became a second mentor to Choibalsan.

While the group of seven continued their lobbying efforts in Soviet Russia, forces commanded by the anti-Bolshevik Russian warlord Roman von Ungern-Sternberg invaded Mongolia from the east and ejected occupying Chinese garrisons from Khüree in February 1921. No longer faced with directly confronting the Chinese in Mongolia, the Soviets finally threw their backing behind the Mongolian revolutionaries. Choibalsan and Sükhbaatar relocated to Troitskosavsk (modern-day Kyakhta on the Russian-Mongolian border) to coordinate revolutionary activities and recruit Mongolian fighters. Choibalsan secretly ventured as far as Khüree to consult with MPP supporters, enlist fighters, and spirit members of Sükhbaatar's family back to Troitskosavsk.

At a Soviet-organized MPP conference held secretly in Troitskosavsk from 1 to 3 March 1921 (subsequently regarded as the first congress of the Mongolian People's Revolutionary Party), Choibalsan was elected a member of the provisional revolutionary government. He was also appointed Political Commissar (Deputy Chief and chief propagandist) of the Mongol Ardyn Huv'sgalt Tsereg (Mongolian: Монгол Ардын Хувьсгалт Цэрэг), or the Mongolian People's Army, commanded by Sükhbaatar.

Defeat of Ungern-Sternberg
Within days, Sükhbaatar's Mongolian partisan army (now numbering 400 men) defeated the larger but demoralized Chinese garrison that had fled to Kyakhta Maimaicheng (modern-day Altanbulag). Joint Mongol and Red Army forces directly confronted Ungern's troops in a series of battles near Troitskosavsk from late May to mid-June. Choibalsan took command of a Mongolian detachment based in Tariat, in modern-day Arkhangai province and, together with the Russian forces commanded by Petr Efimovich Shchetinkin, fought right guard actions in western Mongolia in support of the main Russian-Mongolia advance through modern-day Selenge and Töv provinces. After small skirmishes with Ungern's remaining guard units, the joint Russian-Mongol force entered Khüree unchallenged on 6 July 1921. Choibalsan pursued remnants of Ungern's army and was likely on hand at Ungern's capture by Shchetinkin on 22 August 1921.

Rise to power
After the revolution, Choibalsan remained Deputy Chief of the Mongolian People's Army while also being elected Chairman of the Mongolian Revolutionary Youth League (MRYL). Despite his credentials as one of the MPP's founding members, he failed to advance beyond second-tier government posts throughout the 1920s. His heavy drinking, womanizing, and violent temperament alienated him from party leaders and at one point in the early 1930s he was temporarily demoted from being Minister of Foreign Affairs to the role of simple Museum Director. While he often gravitated towards the leftist faction of the party, he was suspected of being a rightist in what little mention is made of him in Soviet and Mongolian reports of the era. Choibalsan himself did not include many of his own speeches from this period in his collected works, indicating his role during this period was not a prominent one. It was not until members of the Soviet security apparatus such as Soviet Commissar for Defense Kliment Voroshilov took note of Choibalsan's political usefulness in the late 1920s and early 1930s that his career prospects began to improve.

Purge of Bodoo
In late 1921, Choibalsan's MRYL foot soldiers carried out Prime Minister Bodoo's modernization campaign of forcibly cutting off "feudal" ornaments from Mongolian clothing (large cuffs, women's jewelry, long hair etc.). The angry public backlash led to Bodoo's purge and eventual execution in August 1922 while Choibalsan was stripped of both full party membership and his position of as deputy commander of the Mongolian military. Only Sükhbaatar's intervention saved him from Bodoo's fate. Choibalsan was sent to a Moscow Russian Military Academy after Sükhbaatar's death in 1923 and when he returned to Ulaanbaatar a year later was offered his old mentor's former position as Commander in Chief of the People's Revolutionary Troops. He also held positions as a member of the Presidium of the State Great Hural from 1924 to 1928 and as a member of the MPRP Central Committee.

Right Opportunism (1925–28)
At the Third Party Congress in 1924, Choibalsan sided with the leftist leader Rinchingiin Elbegdorj