The British hired the Sepoys (Indian Soldiers) but issued a number of rules that angered the sepoys resulting in their rebellion against the British in 1857. The Lapse doctrine was devised which gave the British a right to veto where a princess adopted heir received the territory. This was against the Hindu tradition of passing down the territorial control from a prince to the other through adoption or blood.
They were against the British Imperial rule that agitated to the colonization of India for its resources.