The Carnatic Treaty was signed on July 26, 1801. Based on the terms of the treaty, the Nawab of Arcot (sometimes called the Nawab of the Carnatic) ceded all his lands to British rule, including the territory of the polygars. He was retained one-fifth of the revenues of the country, amounting to 12 lakhs p.a in exchange.
References
Carnatic Treaty Wikipedia(Text) CC BY-SA