The Mongolian People's Republic (MPR) was a socialist state in Central and East Asia that existed from 1924 to 1992. A one-party state ruled by the Mongolian People's Revolutionary Party, it occupied the historical region of Outer Mongolia and functioned as a satellite state of the Soviet Union for its entire history. Geographically positioned between the Soviet Union and China, the MPR became the world's second socialist state. It is the predecessor of the modern state of Mongolia.
The state was established in 1924 following the Mongolian Revolution of 1921, which was supported by the Soviet Red Army. Under the rule of Khorloogiin Choibalsan, the government aligned closely with Soviet policies, undertaking Stalinist repressions from 1937 to 1939 that resulted in the deaths of over 20,000 people, including the near-total destruction of the country's Buddhist clergy. The MPR's army fought alongside the Soviets in the 1939 Battles of Khalkhin Gol against Japan, and its independence was formally recognized by China after a 1945 referendum.