By 1757 Britain held the upper hand in India after several victories by Robert Clive. In 1758, French reinforcements under Lally had arrived in Pondicherry and set about advancing France's position on the Coromandel Coast, notably capturing Fort St. David. This caused alarm to the British, most of whose troops were with Clive in Bengal. Lally was poised to strike against Madras in June 1758, but short of money, he launched an unsuccessful attack on Tanjore hoping to raise revenue there. By the time he was ready to launch his assault on Madras it was December before the first French troops reached Madras, delayed partly by the onset of the monsoon season. This gave the British extra time to prepare their defences, and withdraw their outposts - boosting the garrison to nearly 4,000 troops.

After several weeks of heavy bombardment, the French were at last starting to make headway against the town's defences. The main bastion had been destroyed, and a breach opened in the walls. The heavy exchange of fire had flattened much of Madras, with most of the town's houses gutted by shells.

On 30 January a Royal Navy frigate ran the French blockade and carried a large sum of money and a company of reinforcements into Madras. Significantly they brought the news that the British fleet under Admiral George Pocock was on its way from Calcutta. When Lally discovered this news he became aware that he would have to launch an all-or-nothing assault to storm the fortress before Pocock arrived. He convened a council of war, where it was agreed to launch an intense bombardment on the British guns, to knock them out of action.

On 16 February, six British vessels carrying 600 troops arrived off Madras. Faced with this added threat, Lally took the immediate decision to break off the siege and withdraw south.