The southern neighbourhood of Mylapore is Chennai's Ur-settlement; in ancient times it traded with Roman, Chinese and Greek merchants. In 1523 the Portuguese established their nearby coastal enclave, San Thome. Another century passed before Francis Day and the British East India Company rocked up in 1639, searching for a good southeast-Indian trading base, and struck a deal with the local Vijayanagar ruler to set up a fort-cum-trading-post at Madraspatnam fishing village. This was Fort St George, built from 1640 to 1653.
The three Carnatic Wars between 1744 and 1763 saw Britain and its colonialist rival France allying with competing South Indian princes in their efforts to get the upper hand over local rulers – and each other. The French occupied Fort St George from 1746 to 1749 but the British eventually triumphed, and the French withdrew to Pondicherry (today Puducherry).
As capital of the Madras Presidency, one of the four major divisions of British-era India, Madras grew into an important naval and commercial centre. After Independence, it became capital of Madras State and then of its successor, Tamil Nadu. The city was renamed Chennai in 1996. Today it's a major IT hub and is often called 'the Detroit of India' for its booming motor-vehicle industry.