3 secret societies working toward the violent overthrow of British rule in India

By 1902, Kolkata (formerly Calcutta) had three secret societies working toward the violent overthrow of British rule in India: one founded by Calcutta student Satish Chandra Basu with the patronage of Calcutta barrister Pramatha Mitra, another led by Sarala Devi, and the third founded by Aurobindo Ghose. Ghose and his brother Barin were among the strongest proponents of militant Indian nationalism at the time.

Nationalist writings and publications by Aurobindo and Barin, including Bande Mataram and Jugantar Patrika(Yugantar), had a widespread influence on Bengal youth and helped Anushilan Samiti to gain popularity in Bengal.

The 1905 partition of Bengal stimulated radical nationalist sentiments in Bengal's Bhadralok community, helping the Samiti to acquire the support of educated, politically conscious and disaffected members of local youth societies

. The Samiti's program emphasized physical training, training its recruits with daggers and lathis (bamboo staffs used as weapons). The Dhaka branch 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. This branch soon overshadowed its parent organisation in Calcutta. Branches of Dhaka Anushilan Samiti emerged in Jessore, Khulna, Faridpur, Rajnagar, Rajendrapur, Mohanpur, Barvali and Bakarganj, with an estimated membership of 15,000 to 20,000. Within two years, Dhaka Anushilan changed its aims from those of the Swadeshi movement to that of political terrorism.

The organisation's political views were expressed in the journal Jugantar, founded in March 1906 by Abhinash Bhattacharya, Barindra, Bhupendranath Dutt and Debabrata Basu.

It soon became an organ for the radical views of Aurobindo and other Anushilan leaders, and led to the Calcutta Samiti group being dubbed the "Jugantar party". Early leaders were Rash Behari Bose, Bhavabhushan Mitra, Jatindranath Mukherjee and Jadugopal Mukherjee. Aurobindo published similar messages of violent nationalism in journals such as Sandhya, Navashakti and Bande Mataram.