In which capacity did this person, who established the Bogd Khan puppet government, serve in the Russian Civil War?
Roman von Ungern-Sternberg Baron Roman Nicolaus Maximilian von Ungern-Sternberg (Russian: Барон Ро́берт-Ни́колай-Максими́лиан Рома́н Фёдорович фон У́нгерн-Ште́рнберг ) (10 January 1886 NS – 15 September 1921) was an anti-Bolshevik lieutenant general in the Russian Civil War and then an independent warlord whose Asiatic Cavalry Division wrested control of Mongolia from the Republic of China in 1921 after its occupation. He was often referred to as Baron Ungern, or simply Ungern.
Yelü Chucai Yelü Chucai (Yeh-lu Chu-tsai; ; Mongolian: Urtu Saqal, 吾圖撒合里, "long beard"; the components of his name also variously spelt Yeh-Lu, Ye Liu, Yeliu, Chutsai, Ch'u-Ts'ai, etc.) (July 24, 1190 - June 20, 1244) was a statesman of Khitan ethnicity with royal family lineage to the Liao Dynasty, who became a vigorous adviser and administrator of the early Mongol Empire in the Confucian tradition. He was the first of Genghis Khan's retainers to formulate policy during the Mongol conquests, and he also introduced many administrative reforms in North China during the reign of Genghis Khan and his successor Ögedei.