Anushilan Samiti
Anushilan and Jugantar each were organised on different lines, reflecting their divergence. "Anushilan Samiti" was centrally organised, with a rigid discipline and vertical hierarchy. Jugantar, was more loosely organised as an alliance of groups, acting under local leaders that occasionally coordinated their actions together. The prototype of Jugantar's organisation was Barin Ghosh's organisation set up in 1907, in the run-up to the Manicktolla conspiracy. It sought to emulate the model of Russian revolutionaries that was described by Frost. The regulations of the central Dhaka organization of the "Anushilan Samiti" were written down, and reproduced and summarised in government reports. According to one estimate, the Dacca Anushilan Samiti had at one point 500 branches, mostly in the eastern districts of Bengal, with 20,000 members. Branches were opened later in the western districts, Bihar, and the United Provinces. Shelters for absconders were established in Assam and in two farms in Tripura. Organisational documents shows a primary division between, on the one hand the two active leadersBarin Ghosh and Upendranath Bannerjee, and the rank-and-file on the other. Higher leaders including Aurobindo were supposed to be known only to the active leaders. Erstwhile members of "Anushilan", particularly those of the Maniktala group, had suggested that the each group were interconnected with a vast web of secret societies throughout British India. However historian Peter Heehs concludes the links between provinces were limited to contacts between a few individuals like Aurobindo who was familiar with leaders and movements in Western India. He concludes the Maniktala society had links between the other groups and the Manicktalla society, such as the Anushilan and Atmannati Samitis, were more often competitive than co-operative. An internal circular of circa 1908 written by Pulin Behari Das, describes the division of the organisation in Bengal, which largely followed British administrative divisions, with central "Samitis" linked with a few small Samitis.
Bagha Jatin
Several sources mention Jatin as being among the founders of the Anushilan Samiti in 1900, and as a pioneer in creating its branches in the districts. According to Daly's Report: "A secret meeting was held in Calcutta about the year 1900 [...] The meeting resolved to start secret societies with the object of assassinating officials and supporters of Government [...] One of the first to flourish was at Kushtea, in the Nadia district. This was organised by one Jotindra Nath Mukherjee ["sic"!].". Nixon reports further : "The earliest known attempts in Bengal to promote societies for political or semi-political ends are associated with the names of the late P. Mitter, Barrister-at-Law, Miss Saralabala Ghosal and a Japanese named Okakura. These activities commenced in Calcutta somewhere about the year 1900, and are said to have spread to many of the districts of Bengal and to have flourished particularly at Kushtia, where Jatindra Nath Mukharji ["sic"!] was leader." Bhavabhushan Mitra's written notes precise his presence along with Jatindra Nath during the first meeting. A branch of this organisation (Anushilan Samiti), was to be inaugurated in Dacca. In 1903, on meeting Sri Aurobindo at Yogendra Vidyabhushan's place, Jatin decides to collaborate with him and is said to have added to his programme the clause of winning over the Indian soldiers of the British regiments in favour of an insurrection. W. Sealy in his report on "Connections with Bihar and Orissa" notes that Jatin Mukherjee "a close confederate of Nani Gopal Sen Gupta of the Howrah Gang (...) worked directly under the orders of Aurobindo Ghosh."