The occupation of Outer Mongolia (also known as the Chinese invasion of Mongolia) by the Beiyang government of the Republic of China after the revocation of Outer Mongolian autonomy () began in October 1919 and lasted until 18 March 1921, when Chinese troops in Urga were routed by Baron Roman von Ungern-Sternberg's White Russian (Buryats, Russians etc.) and Mongolian forces. These, in turn, were defeated by the Red Army and its Mongolian allies by June 1921.
Although the Beiyang government abolished the autonomy of the Bogd Khanate in Outer Mongolia and then expanded its occupation to include Uryankhay Krai (Tuva), it was unable to consolidate its rule over both regions.
Background In December 1911, during the Xinhai Revolution, Outer Mongolia declared independence from the Qing dynasty in the Mongolian Revolution of 1911. Mongolia became a de facto absolute theocratic monarchy led by the Bogd Khan. However, the newly established Republic of China claimed inheritance of all territories held by the Qing dynasty and considered Outer Mongolia as part of its territory. This claim was provided for in the Imperial Edict of the Abdication of the Qing Emperor signed by the Empress Dowager Longyu on behalf of the six-year-old Xuantong Emperor: "the continued territorial integrity of the lands of the five races, Manchu, Han, Mongol, Hui, and Tibetan into one great Republic of China." The Provisional Constitution of the Republic of China adopted in 1912 specifically established frontier regions of the new republic, including Outer Mongolia, as integral parts of the state.
In the 1915 tripartite Kyakhta Agreement, the Russian Empire (which had strategic interests in Mongolian independence but did not want to completely alienate China), the Republic of China and the Bogd Khanate of Mongolia agreed that Outer Mongolia was autonomous under Chinese suzerainty. However, in the following years Russian influence in Asia waned due to the First World War and, later, the October Revolution. Since 1918, Outer Mongolia was threatened by the Russian Civil War, and in summer 1918 asked for Chinese military assistance, which led to the deployment of a small force to Urga. Grigory Semyonov led the Buryats and Inner Mongols in spearheading a plan to create a pan-Mongol state. Meanwhile, some Mongol aristocrats had become more and more dissatisfied with their marginalization at the hands of the theocratic Lamaist government, and, also provoked by the threat of the Outer Mongolia's independence from the pan-Mongolist movement of Grigory Semyonov in Siberia, were ready to accept Chinese rule by 1919.Thomas E. Ewing, "Russia, China, and the Origins of the Mongolian People's Republic, 1911-1921: A Reappraisal", in The Slavonic and East European Review, Vol. 58, No. 3 (Jul., 1980), p. 406ff According to an Associated Press dispatch, some Mongol chieftains signed a petition asking China to retake administration of Mongolia and end Outer Mongolia's autonomy. Since they opposed the Bogd Khan and his clerics, Mongol nobles agreed to abolish Mongol autonomy and reunite with China under an agreement with 63 stipulations signed with Chen Yi () in August–September 1919. The pan-Mongolist initiative of Grigory Semyonov led by Buryats and Inner Mongols was rejected by the Khalkha Mongol nobles of Urga, so the Khalkha nobles instead assured the Chinese under Chen Yi that they were against it. The prospect of ending Mongol autonomy and having Chinese troops stationed in Niialel Khuree, Altanbulag, Uliyasutai, and Khovd was permitted by the Mongolian government in response to the Japanese-backed Buryatia pan-Mongol movement.
An ally of the Chinese government, the Qinghai-born Monguor Gelugpa Buddhist Lama leader Sixth Janggiya Khutughtu was against the autonomy of Outer Mongolia.
Causes
The invasion of Mongolia was the brainchild of Chinese Prime Minister Duan Qirui, who engineered China's entry into World War I. He took out several large loans from the Japanese government, including the Nishihara Loans. He used the money to create the "War Participation Army", ostensibly to battle the Central Powers. His rivals knew that the purpose of the army was really to crush internal dissent. It existed outside the Ministry of the Army and was controlled by the "War Participation Bureau", which he led, and it was staffed entirely by his Anhui clique. President Feng Guozhang, Duan's rival, had no control, despite constitutionally being commander-in-chief. When the war ended without a soldier stepping foot abroad, his critics demanded the disbanding of the War Participation Army. Duan had to find a new purpose for his army. Mongolia was chosen for several reasons: Duan's envoys to the 1919 Paris Peace Conference were unable to prevent the German concession in Shandong (Kiautschou Bay Leased Territory) being transferred to Japan, which caused the Chinese nationalist May Fourth Movement to target his policies. His reputation as a patriot was discredited. Reintegrating Mongolia would reverse the situation. The Constitutional Protection War was fought to a bloody standstill in Hunan. Using his army for another risky attempt to retake southern China from the rebels was undesirable. The Russian Civil War left Mongolia without a foreign protector. An easy victory would boost Duan's stature. The longstanding Prime Minister of Mongolia, Tögs-Ochiryn Namnansüren, died in April 1919 and left the country's ruling elite deeply divided over a successor. Other Mongolian elites, such as Sodnomravdan, Gombosüren, Chagdarjav, Gonchigsüren, Dashnyam and Handdorj had also died of unknown causes.
Invasion
The pro-Japanese Anhui clique leader Xu Shuzheng led the military occupation of Mongolia in violation of Chen Yi's agreement signed with the Mongol nobles because he wanted to use Mongolia as his own fief. Anhui clique was also known as Anfu group. Some authors believe that the Anfu Club was bribed by Japan to implement in Mongolia the strategies of Japan.
The War Participation Army was renamed the Northwestern Frontier Army. Duan gave control of it to his right-hand man, Xu Shuzheng, a member of the pro-Japanese Anhui clique in the Chinese government. They announced that the expedition was at the invitation of several Mongolian princes to protect Mongolia from Bolshevik incursions. It was supposed to begin in July 1919, but the train broke down. In October, Xu led a spearhead group of 4,000 that quickly captured Niĭslel Khüree without resistance. Another 10,000 troops followed to occupy the rest of the country. The successful invasion was met with acclaim throughout China, even by Duan's rival Sun Yat-sen leader of the southern government, although Sun's telegram could be interpreted sarcastically. It is supposed that the Japanese were the ones who ordered the pro-Japanese Chinese warlords to occupy Mongolia to halt a possibly revolutionary spillover from the Russian revolutionaries into Mongolia and Northern China; after the Chinese had completed the occupation, the Japanese abandoned them and left them on their own. This data is not confirmed by archival documents, though, which indicate that the occupation of Outer Mongolia was an initiative of the Anhui-led Chinese government caused by the weakening of Russia by the Russian Revolution and civil war.Kuzmin, S.L. (2011). The History of Baron Ungern. An Experience of Reconstruction. Moscow: KMK Sci. Press, p. 121-141, ISBN 978-5-87317-692-2 Manlaibaatar Damdinsüren said that, "I can defend Mongolia from China and Red Russia."
In 1919, the Mongolian Council of Khans was addressed to by Xu Shuzheng in a condescending speech. In February 1920, Xu presided over a very humiliating ceremony in which the Bogd Khan and other leaders were forced to kowtow before him and the Five Races Under One Union flag. That event marked the beginning of active resistance against Chinese rule, which coalesced into the Mongolian People's Party.
Domestic politics in China soon changed the situation dramatically. The invasion had caused alarm for Zhang Zuolin, the powerful warlord of Manchuria, who was upset that such a large army was moved so close to his territory. He joined the chorus of critics such as Cao Kun and Wu Peifu calling for the removal of the Anhui clique. In July, they forced President Xu Shichang to remove Xu Shuzheng from his position. In response, Xu Shuzheng moved the bulk of his forces to confront his enemies in China. Both he and Duan Qirui were defeated in the ensuing Zhili–Anhui War. That left only a few Chinese troops in Mongolia without their leadership.
Many of the Chinese troops during the occupation were Tsahar (Chahar) Mongols from Inner Mongolia, which was a major cause for animosity between Outer Mongols (Khalkhas) and Inner Mongols. But the main animosity was directed to Chinese soldiers who were not suitably paid by the Chinese Government. This led to profound looting and murdering of Mongols by Chinese troops in Urga and elsewhere.Kuzmin, S.L. (2011). The History of Baron Ungern. An Experience of Reconstruction. Moscow: KMK Sci. Press, p. 164-165, ISBN 978-5-87317-692-2Kuzmin, S. L. 2016. Theocratic Statehood and the Buddhist Church in Mongolia in the Beginning of the 20th Century. Moscow: KMK Sci. Press, p. 147-148, ISBN 978-5-9907838-0-5
The Tüsheet Khan Aimag's Prince, Daichin Chin Wang, was a supporter of Chinese rule, but his younger brother Tsewang was a supporter of Ungern.
The Chinese sent a honghuzi-led band of Chahar Inner Mongols to fight against the Outer Mongols, but the Tushegoun Lama killed them. Both the Chinese army and Ungern's force contained Chahar Inner Mongol soldiers, who participating in kidnapping local Outer Mongol women in addition to looting and mutilating the Outer Mongols. The plundering Inner Mongol Chahars were recruited by the Chinese High Commissioner Wu Tsin Lao with the deliberate knowledge that they would engage in looting. Deserters, including Russians, from Ungern's forces were punished or killed by the Chahar Inner Mongols in Ungern's army. The Soviet Red Army crushed the Chahar Mongol unit of Ungern's forces.
In October, the White Russian Baron Roman von Ungern-Sternberg swept into Mongolia from the north, fought many battles against the Chinese garrison stationed in Urga, and captured it in February 1921. There, he defeated the Chinese forces and restored Bogd Khan as monarch. Around the same time, the MPP engaged in its first battle against Chinese troops. After the defeat of the Chinese army, 2000 Chinese petitioned the Living Buddha to enlist in his legions. They were accepted and formed into two regiments, which wore as insignia the old Chinese silver dragons.
The reconquest of Outer Mongolia was assigned to Zhang Zuolin. A joint MPP-Red Army expedition led by Soviet Red commanders and Damdin Sükhbaatar defeated Ungern in August. One of Soviet regiments against Ungern was led by Konstantin Konstantinovich Rokossovsky. Tensions leading up to the First Zhili–Fengtian War and the apparent victory of the Bolsheviks in the Russian Civil War led to the end of China's involvement. Reincarnations, abbots and lamas were imprisoned or executed by the Mongolian People's Party led by the Soviet Bolsheviks. China rejected the Soviet intervention.