True Left

Continuing from:

https://trueleft.createaforum.com/true-left-vs-false-left/war/msg15051/#msg15051

besides Outer Manchuria being directly stolen by Russia, who was really behind the breakaway of Mongolia? Answer:

https://en.wikipedia.org/wiki/Mongolian_Revolution_of_1921

Although nominally independent, the Mongolian People's Republic was a satellite state of the Soviet Union until a third Mongolian revolution in January 1990.
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Early in 1919, Grigori Semyonov, a White Guard general, had assembled a group of Buryats and Inner Mongols in Siberia for the formation of a pan-Mongolian state. The Khalkhas were invited to join, but they refused. Semyonov threatened an invasion to force them to participate. This threat galvanized the lay princes, who now saw a larger opportunity: the end of theocratic rule. In August, the Mongolian Foreign Minister approached Chen Yi with a message from the "representatives of the four aimags" (i.e., the Khalkhas) with a request for military assistance against Semyonov. More importantly, perhaps, it contained a declaration that the Khalkhas were unanimous in their desire to abolish autonomy and restore the previous Qing system.
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Russian expatriates in Urga had elected a revolutionary "Municipal Duma", headed by Bolshevik sympathisers, which had learned of the Consular Hill group. In early March 1920, the Duma was sending one of its members, I. Sorokovikov, to Irkutsk. It decided that he should also take a report with him about these Mongolians. Sorokovikov met with representatives of the two groups. On his return to Urga in June, he met with them again, promising that the Soviet government would provide "assistance of all kinds" to the Mongolian "workers". He invited them to send representatives to Russia for further discussions.[20]

A new sense of purposefulness now animated both groups. They had maintained a wary distance from one another, perhaps because of their different agendas—the Consular Hill group espousing a rather progressive social program while the East Urga group was more nationalistic in its goals—and there had been little cooperation between the two. The Soviet invitation changed that. The two groups met on 25 June, and formed the "Mongolian People's Party" (renamed later the Mongolian People's Revolutionary Party), adopted a "Party Oath", and agreed to send Danzan and Choibalsan as delegates to Russia.[21]

Danzan and Choibalsan arrived in Verkhneudinsk, the capital of the pro-Soviet Far Eastern Republic, in the first part of July. They met with Boris Shumyatsky, then acting head of the government. Shumyatsky knew little about them, and for three weeks dodged their demands for a speedy Soviet decision whether or not to provide military assistance to the Mongolians against the Chinese. Finally, perhaps at Shumyatsky's suggestion, they sent a telegram to members of the MPP in Urga with a coded message that they should obtain a letter, stamped with the seal of the Bogd Khan, formally requesting Soviet assistance.
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After several meetings with Soviet authorities in Omsk, the Mongolian delegation was told that such an important matter could be decided only in Moscow. Danzan and his compatriots left for Moscow, arriving in about mid-September. For over a month they met frequently but inconclusively with Soviet and Comintern officials.

A White Guard invasion of Mongolia under Baron Roman von Ungern-Sternberg, however, forced the Soviet government into action. In late October to early November 1920, around 1,000 troops under his command had laid siege to the Chinese garrison in Urga numbered about 7,000.
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The Chinese garrison in Urga, however, successfully repulsed von Ungern-Sternberg's attack. This altered the Soviet strategy. The army of the Far Eastern Republic was already exhausted. Only the Fifth Army of the Reds was left on the eastern front, and already by late 1920 many of its more experienced units had either been demobilized, or sent west to fight in Poland, or assigned to the labor front, where they were needed to repair the badly damaged Siberian economy.[27] Thus, when the Chinese repulsed von Ungern-Sternberg, the Soviets on 28 November withdrew their order for an invasion.[28]

However, von Ungern-Sternberg launched a second attack in early February 1921. This time he was successful. Chinese soldiers and civilians fled the city in panic. With the fall of Urga, the Chinese administrations and military garrisons at Uliastai and Khovd departed quickly for Xinjiang. The Bogd Khan was restored as Mongolian monarch by von Ungern-Sternberg. The Bogd Khan and his government were also restored, and a solemn ceremony held on 22 February.
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News of von Ungern-Sternberg's seizure of Urga again influenced Soviet plans. A plenary session of the Comintern in Irkutsk on February 10 passed a formal resolution to aid the "struggle of the Mongolian people for liberation and independence with money, guns and military instructors".[29] With Soviet support, the MPP was now a serious contender for power. The Party, hitherto rather amorphous and loosely connected, required better organisational and ideological definition. A party conference (subsequently regarded as the first congress of the Mongolian People's Revolutionary Party) met secretly on 1–3 March at Kyakhta. The first session was attended by 17 persons, the second by 26. The Party approved the creation of an army command staff headed by Sükhbaatar with two Russian advisors, elected a central committee chaired by Danzan with one representative from the Comintern, and adopted a party manifesto composed by the progressive Buryat Jamsrangiin Tseveen.[30] On 13 March, a provisional government of seven men was formed, soon to be headed by Bodoo. On 18 March, the Mongolian guerrilla army, its ranks now enlarged to 400 through recruitment and conscription, seized the Chinese garrison at Kyakhta Maimaicheng (the Chinese portion of Kyakhta). A new confidence now animated the Party. It issued a proclamation announcing the formation of the government, the expulsion of the Chinese, and the promise to convene a congress of "representatives of the masses" to elect a permanent government.[31]

About ultra-Turanist von Ungern-Sternberg:

https://en.wikipedia.org/wiki/Roman_von_Ungern-Sternberg

He also had Hungarian roots and claimed descent from Batu Khan, Genghis Khan's grandson, which played a role in his dream of reviving the Mongol Empire.[4]
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As a boy, Ungern-Sternberg was noted for being such a ferocious bully that even the other bullies feared him and several parents forbade their children from playing with him as he was a "terror".[7] Ungern was well known for his love of torturing animals, and at the age of 12 he tried to strangle to death his cousin's pet owl for no particularly good reason other than his cruelty towards animals.[7]
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Ungern-Sternberg believed that return to monarchies in Europe was possible with the aid of "cavalry people" – meaning Russian Cossacks, Buryats, Tatars, Mongols, Kyrgyz, Kalmyks, etc.[10]
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In 1905, he left the school to join the fighting in eastern Russia during the Russo-Japanese War, but it is unclear whether he participated in operations against the Japanese or if all military operations had ceased before his arrival in Manchuria,[13] although he was awarded the Russo-Japanese War Medal in 1913.[14]
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There is a widespread view that he was viewed by Mongols as the incarnation of the "God of War" (the figure of Jamsaran in Tibetan and Mongol folklore). Although many Mongols may have believed him to be a deity or at the very least a re-incarnation of Genghis Khan, Ungern was never officially proclaimed to be any of those incarnations.[20]

After graduating, he served as an officer in eastern Siberia in the 1st Argunsky and then in the 1st Amursky Cossack regiments, where he became enthralled with the lifestyle of nomadic peoples, such as the Mongols and Buryats.
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Ungern was an excellent horseman, who earned the respect of the Mongols and the Buryats because of his skill at riding and fighting from a horse and for being equally adept at using both a gun and his sword.[25]