This year marks the 150 years since the outbreak of the revolt against imperialist rule, which signalled the writing was on the wall for British rule
See current news of nationalist celebrations in India
Also wiki background on the uprising
The rebellion or the war for independence had diverse political, economic, military, religious and social causes.The sepoys (from shepai, Bengali for soldier, used for native Indian soldiers) of the Bengal Army had their own list of grievances against the Company Raj, mainly caused by the ethnic gulf between the British officers and their Indian troops. It was also rumoured that the British had started to issue new gunpowder cartridges that had cow and pig fat on them, which insulted both Hindus and Muslims. Other than Indian units of the British East India Company's army, much of the resistance came from the old aristocracy, who were seeing their power steadily eroded under the British.