Chandra Shekhar Sitaram Tiwari (23 July 1906 – 27 February 1931), popularly known as Chandra Shekhar Azad, was an Indian revolutionary who reorganised the Hindustan Republican Association (HRA) under its new name of Hindustan Socialist Republican Association (HSRA) after the death of its founder, Ram Prasad Bismil, and three other prominent party leaders, Roshan Singh, Rajendra Nath Lahiri and Ashfaqulla Khan.