Briefly explain the immediate cause of the Great Revolt.

The immediate cause was the introduction of the GREASED CARTRIDGES of the new Enfield rifle in 1856.

The cartridges had to be BITTEN OPEN before loading, and a rumour spread that they were greased with the fat of COWS AND PIGS. The cow is sacred to Hindus and the pig forbidden to Muslims, so biting the cartridge meant defilement for both communities alike. The sepoys concluded that the British meant to destroy their religion and convert them to Christianity.

The protest began at Barrackpore, where MANGAL PANDEY refused the cartridge and fired at his officers on 29 March 1857; he was hanged on 8 April. When 85 sepoys at MEERUT refused the cartridges and were sentenced to long imprisonment, their comrades rose on 10 MAY 1857 and marched to Delhi — and the Revolt had begun.

Three marks: the cartridge and the rumour, why it offended BOTH communities, and the actual outbreak. The crucial word is BITTEN — without it the offence makes no sense, and candidates who omit it lose the first mark. The names and dates earn the third mark: Mangal Pandey at Barrackpore (29 March 1857) and the Meerut mutiny (10 May 1857). Since the question asks the IMMEDIATE cause, the answer must end with the outbreak, not with general discontent.