When the city of Madras capitulated to the French following the Battle of Madras in 1746, Dupleix opposed that the town be returned under British rule, thus violating the treaty signed by La Bourdonnais. He then sent an expedition against Fort St David (1747), which won over the Nawab of Arcot, ally of the British. Dupleix again attempted the capture of Fort St David, and this time succeeded.