B. R. Ambedkar

Bhimrao Ramji Ambedkar (14 April 1891 – 6 December 1956), popularly known as Dr. Babasaheb Ambedkar was an Indian jurist, economist, politician and social reformer. He inspired the Dalit Buddhist Movement and campaigned against social discrimination against Untouchables (Dalits), and also supported the rights of women and labour. He was independent India's first law minister, the principal architect of the Constitution of India.
In 1956, in Deekshabhoomi, he initiated a mass conversion of Dalits, converting to Buddhism with 600,000 supporters. He revived Buddhism in India. Ambedkar is regarded as a bodhisattva, and the Maitreya, among the Navayana Buddhists.
In 1990, the Bharat Ratna, India's highest civilian award, was posthumously conferred upon Ambedkar. Ambedkar's legacy includes numerous memorials and depictions in popular culture. Ambedkar's legacy as a socio-political reformer had a deep effect on modern India.
Ambedkar was voted "the Greatest Indian" in 2012 by a poll organised by History TV18 and CNN IBN, ahead of Vallabhbhai Patel and Jawaharlal Nehru.
Ambedkar Jayanti (Ambedkar's birthday) is an annual festival celebrated on 14 April, which is celebrated not only in India but all over the world. Ambedkar Jayanti is celebrated as an official public holiday throughout India. The United Nations celebrated Ambedkar Jayanti in 2016, 2017 and 2018.
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