This book studies the regional tradition of mathematics in the Tamil-speaking areas of Southern India. It questions the established nature of Indian history of mathematics, which is based only on the Bhatta-Bhaskara tradition. Instead, it brings in practitioners like village accountants and school teachers as primary agents in the practice of mathematics. The author studies these hitherto unexplored historical sources and presents them in a new light. He talks about mathematics at the workplace, at the school, and at the village square in precolonial Tamil society. Finally, the author studies what happened to these practices when encountered by the colonial revenue administration and brings out a social history of mathematics in India.