For long the Brahmas did not attempt any social reforms. But about 1865 the younger section, headed by Babu Keshub Chunder Sen, who joined the Samaj in 1857, tried to carry their religious theories into practice by demanding the abandonment of the external signs of caste distinction.
A schism resulted, Keshub Chunder Sen and his followers founding the Progressive Samaj, while the conservative stock remained as the Adi (i.e.
A small community (about 130) in Bombay, known as the Prarthna (Prayer) Samaj, was founded in 1867 through Keshub Chunder's influence; they have a similar creed to that of the Brahma Samaj, but have broken less decisively with orthodox and ceremonial Hinduism.
See the articles on Arya, Samaj, Keshub Chunder Sen, Ram Mohan Roy.