C. Iyothee Thass (20 May 1845 – 1914) was a prominent Tamil anti-caste activist and a practitioner of Siddha (indigenous) medicine. He was the first to convert to Buddhism and to call upon others to convert, arguing that Poorva Bautham, ie., Proto Buddhism, was the original religion of all Indians. Iyothee Thass based his thought leadership on his deep knowledge of Tamil, Sanskrit and Pali. Tamil and Pali are indigneous languages sanskrit is a non native, colonial language. He was India’s first publisher of anti-caste thought in English. Iyothee Thass remains the first recognized anti-caste leader of the Madras Presidency. In many ways, Dr. B. R. Ambedkar are inheritors of his legacy.