On 24 October 1746, the Battle of Adyar (also known as the Battle of the Adyar River) saw a remarkably small force of the French East India Company - some 350 French soldiers and 700 French-trained Indian sepoys - defeat an army of around 10,000 infantry and cavalry sent by the Anwaruddin Khan, the Nawab of the Carnatic, near the Adyar River, south of Madras.

The confrontation occurred after the French had captured the British-held Fort St. George in Madras, and vowed to hand it over to the Nawab - a promise they later reneged on. 
The Nawab’s army, led by his son Mahfuz Khan, massed north of the river to block French reinforcement from Pondicherry. The French, under Swiss engineer Major Louis Paradis, crossed the shallow river and launched a disciplined volley and bayonet charge that broke the Indian line by evening. 

Historians regard this battle as a tipping point: for the first time in India a small disciplined European-force demonstrated that flintlock muskets, mobile artillery and trained troops could defeat large native armies — signalling the entry of modern warfare into the subcontinent.