Born to a respectable family in Calcutta on 19 November 1838, Keshab Chandra Sen was one of the most famous social reformers of India and took the leadership of the Brahmo Samaj during the absence of Debendranath Tagore. A strong votary of widow remarriage, Keshab Chandra Sen started Bamabodhini Patrika, a journal for women.
Keshab Chandra Sen launched several radical reforms, such as giving up of caste names, advocating inter caste marriage and launched movement against the social vices prevailing at that time like child marriage. These radical reforms resulted in the first schism in the Brahmo Samaj. The original Brahmo Samaj, founded by Raja Ram Mohan Roy, came to be known as Adi Brahmo Samaj and the other, the Brahmo Samaj of India was established by Keshab Chandra Sen in 1867.
In 1870 Keshab Chandra Sen founded the India Reform Association which succeeded in persuading the British Government to enact the Native Marriage Act of 1972 (popularly known as Civil Marriage Act) legalizing the Brahmo marriages and fixing the minimum marriageable age for boys and girls.
It was under the advice of Keshab Chandra Sen that the reformist Dayanand Saraswati began to use Hindi for his writings and teachings.