By what I think I know, Britain had relatively little apart from a strong navy that could lead to their Indic hegemony. India was led by several strong rulers that all had access to gunpowder and muskets. They were fighting on home territory whereas Britain shipped over tiny numbers of troops, relatively speaking. I can understand that maybe Britain used local diplomacy successfully and backed the right sides to begin with, but surely once they started becoming a threat, the balance of power would lead to some coalition forming? In essence, why/how did a technologically equal, tiny nation come to rule a vast subcontinent?