Manabendra Nath Roy (21 March 1887 – 26 January 1954), born Narendra Nath Bhattacharya, was an Indian revolutionary, radical activist and political theorist. Roy was a founder of the Mexican Communist Party and the Communist Party of India. He was also a delegate to congresses of the Communist International and Russia's aide to China. Following the rise of Joseph Stalin, Roy left the mainline communist movement to pursue an independent radical politics.