Anushilan Samiti
By 1902, Calcutta had three secret societies working toward the violent overthrow of British rule in India. One was founded by Calcutta student Satish Chandra Basu with the patronage of Calcutta barrister Pramatha Mitra, another was led by Bengali woman Sarala Devi and the third was founded by Aurobindo Ghosh. Ghosh was one of the strongest proponents of militant Indian nationalism at the time. By 1905 the work of Aurobindo and his brother, Barin, enabled Anushilan Samity to spread throughout Bengal. Nationalist writings and publications by Aurobindo and Barin, including "Bande Mataram" and "Jugantar", had a widespread influence on Bengal youth. The 1905 partition of Bengal stimulated radical nationalist sentiments in Bengal's Bhadralok community, helping Anushilan acquire a support base of educated, politically-conscious and disaffected members of local youth societies. Its program emphasized physical training, training its recruits with daggers and "lathis" (bamboo staffs used as weapons). The Dhaka branch of Anushilan was led by Pulin Behari Das, and branches spread throughout East Bengal and Assam. More than 500 branches were opened in eastern Bengal and Assam, linked by "close and detailed organization" to Pulin's headquarters at Dhaka. It absorbed smaller groups in the province, soon overshadowing its parent organisation in Calcutta. Branches of Dhaka Anushilan emerged in Jessore, Khulna, Faridpur, Rajnagar, Rajendrapur, Mohanpur, Barvali and Bakarganj. Estimates of Dhaka Anushilan Samiti's reach indicate a membership of 15,000 to 20,000. Within two years, Dhaka Anushilan devolved its aims from the Swadeshi to that of political terrorism.
Jugantar
Jugantar or Yugantar ( "Jugantor") (English meaning "New Era" or more literally "Transition of an Epoch") was one of the two main secret revolutionary trends operating in Bengal for Indian independence. This association, like Anushilan Samiti started in the guise of suburban fitness club. Several Jugantar members were arrested, hanged, or deported for life to the Cellular Jail in Andaman. Thanks to the amnesty after World War I, most of them were released and could give a new turn to their political career, mainly: (a) by joining Deshbandhu's Swarajya or (b) the Communist Party of India; or (c) M. N. Roy's Radical Democratic Party; or (d) later Subhas Chandra Bose's Forward Bloc in the 1930s.This party was established by leaders like Aurobindo Ghosh, his brother Barin Ghosh, Bhupendranath Datta, Raja Subodh Mallik in April 1906. Barin Ghosh and Bagha Jatin were the main leaders. Along with 21 revolutionaries, they started to collect arms, explosives and manufactured bombs. The headquarters of Jugantar was located at 27 Kanai Dhar Lane, then 41 Champatola 1st Lane, Kolkata.