Political history of Sri Aurobindo
Anushilan Samiti was founded as an attempt to organize Bengali youth through a program of physical fitness and spiritual training for a nationalist program. By 1902, Calcutta had three societies working under the umbrella of Anushilan Samity, a society earlier founded by a Calcutta barrister by the name of Pramatha Mitra. These included Mitra's own group, another led by a Bengali lady by the name of Sarala Devi, and a third one led by Aurobindo Ghosh. The Anushilan Samiti had Aurobindo and Deshabandhu Chittaranjan Das as the vice-presidents, Suren Tagore the treasurer. Jatindra Nath Banerjee (Niralamba Swami), Bagha Jatin, Bhupendra Nath Datta (Swami Vivekananda's brother), Barindra Ghosh were among other initial leaders.
By 1905, the work of Aurobindo and his brother Barin Ghosh allowed Anushilan Samity to spread through Bengal.
Pulin Behari Das
In September, 1906, Bipin Chandra Pal and Pramatha Nath Mitra took a tour of the newly created province of Eastern Bengal and Assam. The latter, while delivering his speech, asked them to come forward who were willing to sacrifice their lives for their country and Pulin had stepped forward. Subsequently, he was nominated to organize the Dhaka chapter of the Anushilan Samiti. In October, Pulin founded the Dhaka chapter with 80 young men.