Rinchingiin Elbegdorj (Mongolian: Ринчингийн Элбэгдорж; Russian: Элбе́к-Доржи́ Ринчино, Ėlbek-Dorzhi Rinchino; May 16, 1888 –June 10, 1938) was a Buryat revolutionary who played leading roles in the Outer Mongolian Revolution of 1921 and the early political development of the Mongolian People's Republic.
Elbegdorj was born on May 16, 1888 into a herding family in Barguzinsky District, Transbaikal. He became a communist around 1910 while studying at Saint Petersburg State University. He then moved to Troitskosavsk where he wrote for a local newspaper and traveled throughout Mongolia, becoming involved in clandestine Mongolian revolutionary activities. Elbegdorj befriended a young Khorloogiin Choibalsan in Irkutsk between 1914 and 1918 and became a strong early influence on future Mongolian leader.
By 1920, Elbegdorj's connection to Mongolian revolutionary groups and his expertise on Mongolian affairs made him an indispensable part of Soviet efforts to steer Mongolia's early revolutionary development. In 1920 he organized the first meetings between Mongolian revolutionaries and members of the Revolutionary Military Committee of the Fifth Red Army and acted as the group's Russian interpreter. He also accompanied delegates Soliin Danzan and Dambyn Chagdarjav to Moscow where they met Russian communist leader Nikolay Bukharin. He was also a guiding presence at the first secret meeting of the Mongolian People's Party held in Troitskosavsk from March 1–3, 1921 (later known as the First Party Congress of the MPRP) where the provisional revolutionary government of Mongolia was established.