Most of the princely states were annexed, either directly after battle or by indirect pressures, such as those applied by Lord Dalhousie, which certainly had to do with military might.
Furthermore, although it is nowadays assumed that the Indian National Movement was peaceful, that is only because of the eventual success of the Gandhian method of non-violent protest.
However, the Indian National Movement was indeed partly violent with revolutionary leaders such as Subhash Chandra Bose. Many revolutionary freedom fighters were hanged, and later others were jailed in the Andamans. Even the Quit India movement, spearheaded by Gandhi and party to other forms of non-violent protest (such as the Salt Satyagraha), was couteracted by violence and lathi-charge, not to mention the Amritsar massacre of unarmed protestors.
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