Chennai (also known as, Madras ) is the capital city of the Indian state of Tamil Nadu. Located on the Coromandel Coast off the Bay of Bengal, it is the biggest industrial and commercial centre in South India, and a major cultural, economic and educational centre. Chennai is known as the "Detroit of India" for its automobile industry. Chennai is the fifth-largest city and fourth-most populous metropolitan area in the country and 31st-largest urban area in the world. As a growing metropolitan city in a developing country, Chennai confronts substantial urban pollution, traffic congestion, poverty, overpopulation, and other logistic and socio-economic problems.
The city is host to the third-largest expatriate population in India after Mumbai and Delhi, with 35,000 in 2009 and steadily climbing to 82,790 in 2011. Chennai is the only city in South Asia and India to figure in the "52 places to go around the world" by The New York Times. Tourism guide publisher Lonely Planet has named Chennai as one of the top ten cities in the world to visit in 2015. Chennai is ranked as a beta-level city in the Global Cities Index ahead of Hyderabad and Kolkata. Chennai has also been named in the 'hottest' cities to live in for 2015 by BBC among global cities with a mixture of both modern and traditional values.
The region around Chennai has served as an important administrative, military, and economic centre for many centuries. During 1st century CE, a poet and weaver named Thiruvalluvar lived in the town of Mylapore (a neighbourhood of present Chennai). From 1st century CE until 12th CE the region of present Tamil Nadu and parts of South India was ruled by the Cholas.
Stone age implements have been found near Pallavaram in Chennai. According to the Archaeological Survey of India (ASI), Pallavaram was a megalithic cultural establishment, and pre-historic communities resided in the settlement. The Pallavas of Kanchi built the areas of Mahabalipuram and Pallavaram during the reign of Mahendravarman I. They also defeated several kingdoms including the Cheras, Cholas and Pandyas who ruled over the area before their arrival. Sculpted caves and paintings have been identified from that period. Ancient coins dating to around 500 BC have also been unearthed from the city and its surrounding areas. A portion of these findings belonged to the Vijayanagara Empire, which ruled the region during the medieval period.
Thiruvotriyur is historically important port city, which now forms part of north Chennai. This place was exempted from tax and hence derived the name Votriyur with a sanctified pretext thiru. In this locality there still exists an ancient temple dedicated to Lord Adhipuriswara built or last renovated during King Rajaja III of 13th century CE. The temple could have been in existence long before. There is a stone inscription which informs that dedication of 5 ladies in hereditary to the Lord to do the work of husking of paddy by Tiruvekambamudaiyan Senthamaraikannan alaias vayiratharayan of Virukanbakkam alias Chenninallur. This shows evidence that the name chenninallur was in existence even during 12th century as there still is a popular place/area in chennai called Virukanbakkam. (Proof: Govt Inscriptions Serial No.V:6 ARE Record 1892 No.110 and s.1.1.Vol. IV no.558)
In 1746, Fort St. George and Madras were captured by the French under General La Bourdonnais, the Governor of Mauritius, who plundered the town and its outlying villages. The British regained control in 1749 through the Treaty of Aix-la-Chapelle and strengthened the town's fortress wall to withstand further attacks from the French and Hyder Ali, the Sultan of Mysore. They resisted a French siege attempt in 1759 under the leadership of Eyre Coote. In 1769 the city was threatened by Mysore and the British were defeated by Hyder Ali, after which the Treaty of Madras ended the war. By the late 18th century, the British had conquered most of the region around Tamil Nadu and the northern modern–day states of Andhra Pradesh and Karnataka, establishing the Madras Presidency with Madras as the capital.
After India gained its independence in 1947, the city became the capital of Madras State, which was renamed as Tamil Nadu in 1969. The violent agitations of 1965 against the compulsory imposition of Hindi in the state marked a major shift in the political dynamics of the city and eventually it had a big impact on the whole state. On 26 December 2004, an Indian Ocean tsunami lashed the shores of Chennai, killing 206 people in Chennai and permanently altering the coastline.