Chandernagar was the only French settlement in Bengal. It was captured...
In 1756 war broke out between France and Great Britain, and Colonel Robert Clive of the British East India Company and Admiral Charles Watson of the Royal Navy bombarded and captured Chandernagore (Chandannagar) on 23 March 1757.
Lying ten miles up river from Calcutta, Chandernagore was the administrative centre of the French East India Company. Clive, "determined to eliminate" Siraj ud-Daulah Nawabs of Bengal, chose the capture of the French Fort d'Orleans and Chandernagore, as a first step. The French had a total of 16 guns against the Watson's HMS Kent (1746), HMS Tiger (1747), and HMS Salisbury (1746), and Clive's land forces. Though "the guns of the fort did a great deal of damage", including 37 killed and 74 wounded on the Tiger, the attack was successful.
In order to take the Fort d'Orleans guarding the town, Kent and Tiger managed to edge up the Hooghly river, although the French had tried to block it with sunken ships, booms and chains. When they were close to the fort, they opened fire with all guns, but took a great punishment from the French in the process.
The battle there was one of the many fought between the French and English on the sub-continent during the Seven Years' War. It gave the East India Company effective control of Calcutta and the Bengal hinterland. The French who escaped took shelter with the Nawab, whom Clive shortly afterwards defeated at Plassey. Britain finished the war as the dominant European power in India, and was well-placed to take advantage of the weakening political and economic power of the Moghul Empire. Chandernagore's capture was the first step in the British driving the French from Bengal.