The revolutionary movement for Indian Independence, at first started as a stray incidence at the end of the 18th century but it gradually formed groups in different parts of India. Such Revolurionary groups existed in Tamil Nadu, Maharashtra, Bengal, Orissa, Uttarpradesh, and Punjab. Some more groups were scattered around India since the beginning of 19th century.These groups and individuals had at theirsource of inspiration from Inside and outside India. 
In Bengal three groups at different times and under different leaderships were formed. 1. Anushilan Samity,
2. Jugantar, 3. Bengal Volunteers.
Anushilan Samiti (Bengali: অনুশীলন সমিতি "Self-Culture Association", meaning to follow the teachings of Bankim Chandra Chatterjee) was an armed anti-British organisation in Bengal and the principal secret revolutionary organisation operating in the region in the opening years of the 20st century.
Background :
Impact of European Secret Societies
The revolutionaries of India got inspiration from the secret organisation of diffeent countries of the world at the end of 19th century. Specially,
1. Mazzini and Garibaldi of Italy,
2. Nikolai Chernyshevisky of Russia,
Mazzini of Italy
Garibaldi of Italy