Bogd Khan (c. 1869 20 May 1924) was the ruler (khan) of the Bogd Khaganate of Mongolia from 1911 to 1924, following the country's independence from the Qing dynasty of China after the Xinhai Revolution. Born in Tibet, he was the third most important person in the Tibetan Buddhist hierarchy as the 8th Jebtsundamba Khutuktu, below only the Dalai Lama and Panchen Lama, and therefore also known as the "Bogdo Lama". He was the spiritual leader of Outer Mongolia's Tibetan Buddhism. His wife Tsendiin Dondogdulam, the Ekh Dagina ('Dakini Mother'), was believed to be a manifestation of White Tara.

Nikolai Robert Maximilian Freiherr von Ungern-Sternberg (Russian: Роман Фёдорович фон Унгерн-Штернберг, romanized: Roman Fedorovich fon Ungern-Shternberg; 10 January 1886 – 15 September 1921), often referred to as Roman von Ungern-Sternberg or Baron Ungern, was an anticommunist general in the Russian Civil War and then an independent warlord who intervened in Mongolia against China. A part of the Russian Empire's Baltic German minority, Ungern was an ultraconservative monarchist who aspired to restore the Russian monarchy after the 1917 Russian Revolutions and to revive the Mongol Empire under the rule of the Bogd Khan. His attraction to Vajrayana Buddhism and his eccentric, often violent, treatment of enemies and his own men earned him the sobriquet "the Mad Baron" or "the Bloody Baron".

In February 1921, at the head of the Asiatic Cavalry Division, Ungern expelled Chinese troops from Mongolia and restored the monarchic power of the Bogd Khan. During his five-month occupation of Outer Mongolia, Ungern imposed order on the capital city, Ikh Khüree (now Ulaanbaatar), by fear, intimidation and brutal violence against his opponents, particularly the Bolsheviks. In June 1921, he travelled to eastern Siberia to support anti-Bolshevik partisan forces and to head off a joint Red Army-Mongolian rebel invasion. That action ultimately led to his defeat and capture two months later. He was taken prisoner by the Red Army and, a month later, was put on trial for "counter-revolution" in Novonikolaevsk. After a six-hour show trial, he was found guilty and on 15 September 1921 he was executed.