Braja Kishore Prasad was born on 14 January 1877 in the Siwan district of Bihar. He completed his early years of schooling in Chhapra and then enrolled at the Presidency College in Calcutta to study Law. In those days, in order to popularize education in English, the British introduced a system of management in their provinces, whereby the zamindars built schools and colleges for this purpose. This drastic transformation in the schools of learning was reflected in Prasad. Besides being erudite and liberal, he was a jurist, a social reformer, a freedom fighter, and a philanthropist. He personified the advent of modernity in Bihar.

Long before Gandhiji stepped foot in Champaran, Prasad was already working to redress the plight of the peasants by legal means. He was a bold and outspoken voice for justice, though many were scared to speak out against the government. His efforts resulted in the Settlement Report, which, though it was not particularly helpful to the ryots (peasants), was an indication that the government was aware of their problems.

His meeting with Mahatma Gandhi in 1915 truly inspired him, so much so, that he gave up his legal practice to devote his full attention to the cause of the country’s fight for independence. He was instrumental in Gandhiji's decision to take up the Champaran cause, for which Gandhiji also hand-picked Rajendra Prasad and Anugrah Narayan Sinha as co-leaders. Gandhiji was so moved by Prasad's dedication, that in his autobiography, The Story of My Experiments with Truth, he dedicated an entire chapter to him, titled, "The Gentle Bihari".