The Indian soldiers were dissatisfied with their pay as well as with certain changes in regulations, which they interpreted as part of a plot to force them to adopt Christianity. This belief was strengthened when the British furnished the soldiers with cartridges coated with grease made from the fat of cows (sacred to Hindus) and of pigs (anathema to Muslims). The British replaced the cartridges when the mistake was realized; but suspicion persisted, and in Feb., 1857, began a series of incidents in which sepoys refused to use the cartridges.

On May 10 the sepoys revolted at Meerut; they captured Delhi and proclaimed Bahadur Shah II the emperor of all India. The mutiny spread rapidly through N central India, and, by the end of June, Cawnpore (Kanpur) had fallen to the sepoys of Nana Sahib, and Lucknow was besieged. In repressing the rebellion the British were aided by the loyalty of the Punjab (the Sikhs did not wish to see the restoration of Mughal rule) and the passivity of the south. Troops (largely British) under generals Colin Campbell and Henry Havelock accomplished the reconquest. Delhi was recaptured in Sept., 1857, and Lucknow (which had been abandoned in Nov., 1857) was retaken in Mar., 1858. The rebellion was marked by atrocities on both sides, the British taking savage reprisals for the massacres perpetrated by the rebels.

Despite the army's sometimes savage reconquest, the British government did recognize the urgent need for reform, and in 1858 the East India Company was abolished and rule assumed directly by the British crown. Expropriation of land was discontinued, religious toleration was decreed, and Indians were admitted to subordinate positions in the civil service. However, the rebellion was long remembered with bitterness by the British. Military precautions against further uprisings included increasing the proportion of British to native troops and restricting artillery service to Britons. Although it is too much to say that the mutiny constituted a nationalist uprising, it was at that time that the first stirrings of active Indian nationalism began to be felt.