Long before India gained independence, one defiant voice inside the British Empire dared to call out a colonial massacre - and paid a price for it.

Sir Chettur Sankaran Nair, a lawyer, was one of the few Indians to be appointed to top government posts when the British ruled the country.

In 1919, he resigned from the Viceroy's Council after the Jallianwala Bagh massacre in the northern Indian city of Amritsar in Punjab, in which hundreds of civilians attending a public meeting were shot dead by British troops. On the 100th anniversary of the massacre, then UK Prime Minister Theresa May described the tragedy as a "shameful scar" on Britain's history in India.

Nair's criticism of Punjab's then Lieutenant Governor, Michael O'Dwyer, led to a libel case against him, which helped spotlight the massacre and the actions of British officials.

In a biography of Nair, KPS Menon, independent India's first foreign secretary, described him as "a very controversial figure of his time".

Nair was known for his independent views and distaste for extremist politics, and spoke critically of colonial rule and even of Mahatma Gandhi, the Indian independence hero who is now regarded as the father of the nation.

Menon, who married Nair's daughter Saraswathy, wrote: "Only [Nair] could have insulted the all powerful British Viceroy on his face and opposed Mahatma Gandhi openly."

Nair was not a familiar name in India in recent decades, but earlier this year, a Bollywood film based on the court case, Kesari Chapter 2- starring superstar Akshay Kumar - helped bring attention to his life.

Nair was born in 1857 into a wealthy family in what is now Palakkad district in Kerala state. He studied at the Presidency College in Madras, acquiring a bachelor's degree before studying law and beginning his career as an apprentice with a Madras High Court judge.

In 1887, he joined........

© BBC