Step 1: Place it in the reform-movement timeline:
Brahmo Samaj is widely regarded as the first major organised socio-religious reform movement of modern India, predating later movements like the Arya Samaj.
Step 2: Note its key social campaigns:
Its most significant practical achievements included campaigning against sati (which contributed to its abolition in 1829) and promoting girls' education and widow remarriage.
Final Answer:
Founded in 1828 by Raja Ram Mohan Roy, Brahmo Samaj was modern India's pioneering reform movement, fighting sati, caste rigidity and idol worship while promoting rational monotheism and women's welfare.