Vellore district is one of the 32 districts in the Tamil Nadu state of India. It is one of the six districts that form Tiruvannamalai region of Tamil Nadu. It is one of the biggest district in Tamil Nadu. Vellore City is the headquarters of this district. As of 2011, the district had a population of 3,936,331 with a sex ratio of 1,007 females for every 1,000 males.

Vellore had been under the control of Cholas of Uraiyur, Pallavas, Rashtrakutas of Malkhed, Sambuvarayar, who lived in the territory of Melakadambur which denoted in Ponniyin selvan the rulers of Vijayanagaram, Marathas, the Nawabs of the Carnatic and the British. The Vellore fort, which was probably built during the rule of Chinna Bommi Nayak (1526 to 1595 A.D.), was considered to be a strong fort during the Carnatic war in the 17th century.

The district finds an important place in the Indian freedom struggle. The Sepoy Mutiny of 1806 that took place inside the Vellore fort was seen as a prelude to the Revolt of 1857.

Men from the Vellore District fought in the British India Army and sacrificed their lives in the World Wars. This is recorded in the clock tower in the long bazaar at Vellore, raised in 1920, where an inscription reads “Vellore – From this Village 277 men want to the Great war 1914-18, of them 14 gave up their lives”.

After the Indian independence in 1947, Vellore became a part of the erstwhile Madras state. The modern Vellore District was formerly part of North Arcot District, which was established by the British in the 19th century had Chittoor as its headquarters. On 1 April 1911, district was split into Chittoor district and North Arcot.

On 30 September 1989 the district was split into Tiruvannamalai-Sambuvarayar (present-day Tiruvannamalai) and North Arcot Ambedkar districts. North Arcot Ambedkar District was renamed Vellore District in 1996. Vellore district has many more historical places like Arcot nawab’s Tiruppathur war. Kailasagiri hill is the best example for that: We can see many places on top of the hill and a beautiful Lord Murugan temple is there.

Vellore district has an area of 6077 km². Vellore district lies between 12° 15’ to 13° 15’ North latitudes and 78° 20’ to 79° 50’ East longitudes in Tamil Nadu State.

The average maximum temperature experienced in the plains is 39.5 degree Celsius and the average minimum temperature experienced is 15.6 degree Celsius. The region experiences an average annual rainfall of 795 mm, out of which North East Monsoon contributes to 535 mm and the South West Monsoon contributed to 442 mm.

According to 2011 census, Vellore district had a population of 3,936,331 with a sex ratio of 1,007 females for every 1,000 males, much above the national average of 929.A total of 432,550 were under the age of six, constituting 222,460 males and 210,090 females. Scheduled Castes and Scheduled Tribes accounted for 21.85% and 1.85% of the population respectively. The average literacy of the district was 70.47%, compared to the national average of 72.99%.

The district had 929,281 households. There were 1,689,330 workers, comprising 153,211 cultivators, 254,999 main agricultural labourers, 106,906 in household industries, 845,069 other workers, 329,145 marginal workers, 21,897 marginal cultivators, 136,956 marginal agricultural labourers, 29,509 marginal workers in household industries and 140,783 other marginal workers.