Mikhail Borodin, also known as Michael Borodin and born Mikhail Markovich Gruzenberg (1884-1951), was a Soviet agent who principally operated in Asia, under the auspices of the Comintern. His first political activity in Russia was in the Jewish Socialist League, but he was a Bolshevik by 1905, serving in foreign assignments in the U.S. and Europe in 1918-1920. He returned and rose in the Comintern hierarchy, as well as more general tasks such as translating Lenin's "Communism: a Left-Wing Disorder" into English. In 1921-1922, he focused on Britain, both in the Executive Committee of the Comintern (ECCI) and as an agent, briefly imprisoned, in the U.K. 
He went to China in 1923, where he was the Soviet contact with Sun Yat-sen, and later led a Soviet mission that included Ho Chi Minh. As a deputy to Adolf Joffe, he worked to establish a working Chinese Communist Party, as well as set up the first United Front in China, working with lesser agents such as Ho. 
He was blamed, however, for the failure of Soviet policies that led to the Kuomintang attack on the Soviet embassy, and later for purges of the Chinese Communist Party. Eventually, he fell into disfavor, and, although a recipient of the Order of the Red Banner, was arrested in 1949 and was believed to have died in a prison camp in 1951.
Along with other Soviets in China, such as General Vasily Blyukher (who helped Chiang Kai-shek plan the 1926 "Northern Expedition" to unite China) and other victims of Stalinist repression, he was rehabilitated posthumously in the 1960s and made a model of pro-Soviet behavior in the 1970s.
- Albert L. Weeks (June 21, 1981), "A Hero, Soviet-Style (book review of Borodin, Stalin's Man in China. By Dan N. Jacobs)", New York Times
- Branko M. Lazić, Milorad M. Drachkovitch (1986), Biographical dictionary of the Comintern (Revised Edition ed.), Hoover Institution Press, ISBN 0817984011, p. 39
- June Grasso, Jay P. Corrin, Michael Kort (2004), Modernization and Revolution in China: From the Opium Wars to World Power (Third Edition ed.), M.E. Sharpe, ISBN 0765614472, p. 89
- Mary M. Leder, Laurie Bernstein (2001), My Life in Stalinist Russia: An American Woman Looks Back, Indiana University Press, ISBN 0253338662, p. 75