Arcot, city in southeastern India, in the state of Tamil Nādu. Arcot is located on the Palar River, 105 km (65 mi) southwest of Chennai (formerly Madras). It is the administrative center of the North Arcot District. Arcot has a warm climate and receives between 750 and 1300 mm (30 and 50 in) of rainfall per year. Arcot was once an industrial and commercial center of some importance and is now a local market and administrative center. The city, capital of the Carnatic Kingdom, played an important part in the Carnatic Wars, which were conflicts in India between France and Britain during the 18th century. British captain Robert Clive, who later became governor of Bengal, captured Arcot from the French in 1751 with only a small force of about 500 British and Indian soldiers. This compelled the French to give up their siege of the British-held town of Trichinopoly (now Tiruchirappalli). The French and their Indian allies, numbering 10,000, then laid siege to Clive's forces in Arcot. After an 11-week defense in the citadel of the town, Clive and his small band defeated the French. These and later victories broke French power in southern India and gave the British a stronghold in that region.

In 1780 the frequently contested city was conquered by Haidar Ali, the Muslim prince of India and ruler of Mysore, India. In 1801 the British gained full control of the whole Carnatic region, including Arcot. Population (2001) 126,975.