Brahmo Samaj was founded by Raja Ram Mohan Roy in Kolkata in 1828 as a reformist movement within Hinduism. Its primary objectives included eradicating social and religious evils like Sati, caste system, idolatry, and promoting monotheism and rationalism. After Roy's death, the leadership passed to Debendranath Tagore, and later Keshab Chandra Sen joined. Differences led to a split, with Tagore's group becoming Adi Brahmo Samaj and Sen's group forming Brahmo Samaj of India. Both were distinct versions that emerged from the original movement.