The 1500 Sepoys located in the Vellore garrison mutinied and killed or wounded over 200 of 370 Europeans in the fort, on the fated day of July 10. The Vellore Mutiny was however rapidly smashed due to quick response of Colonel Robert Gillespie (1766-1814). The Colonel, coming from Arcot, sixteen miles away, brought cavalry and horse artillery to Vellore and immediately obliterated out of hand 300 to 400 mutineers. Indian disaffection appeared to have come in opposition to orders by Sir John Cradock, Commander in Chief of the Madras Army. Cradock had ordered the removal of caste marks by the sepoys while on duty and replaced the turban with a new-styled leather headgear.
The presence of the exiled family of the late Tipu Sultan may also have contributed to the current of hostility. Tipu Sultan`s sons were imprisoned at the Vellore fort since 1799. One of Tipu Sultan`s daughters was to be married on July 9 1806. The plotters of the mutiny amassed at the fort under the ruse of attending the wedding. Two hours after midnight, on July 10, the sepoys (soldiers) surrounded the fort and killed most of the British. The rebels seized control by daybreak and raised the flag of the Mysore Sultanate over the fort. Tipu`s second son Fateh Hyder was declared King.
After the incident, the imprisoned royals were transferred to Calcutta. The controversial meddling with social and religious customs of the sepoys was abolished. Flogging also was parted with. Following the mutiny, both Cradock and Lord William Bentinck (1774-1839), Governor of Bombay, were sacked