Dheeran Chinnamalai was one of the main commanders in the Polygar Wars, notably during the Second Polygar War that took place in 18011802. He was trained by French military in modern warfare alongside Tipu Sultan to fight against the British East India company and helped in victories against the British at Chitheswaram, Mazahavalli and Srirangapatna.
After Kattabomman and Tipu Sultan‘s deaths, Chinnamalai sought the help of Marathas and Maruthu Pandiyar to attack the British at Coimbatore in 1800. British forces managed to stop the armies of the allies and hence Chinnamalai was forced to attack Coimbatore on his own. His army was defeated and he escaped from the British forces. Chinnamalai engaged in guerrilla warfare and defeated the British in battles at Cauvery in 1801, Odanilai in 1802 and Arachalur in 1804.
Statues and memorials commemorating Dheeran Chinnamalai exist in Chennai, Tiruchirappalli, Erode and Odanilai. On 31 July 2005, a commemorative postage stamp commemorating him was released by India Post.
Until 1997, Tiruchirapalli division of Tamil Nadu State Transport Corporation was known as Dheeran Chinnamalai Transport Corporation. Until 1996, Karur district was known as Dheeran Chinnamalai district. The headquarters of Erode Municipal Corporation are named after him.