Bhupendranath Datta (1880-1961) – Youngest brother of Swamiji in pre-monastic life, scholar, patriot, propagated Marxist sociology, author of many books. Born in Calcutta on 4.9.1880. Passed Entrance examination from Metropolitan Institution (1898). Engaged in revolutionary activities from the age of 23. Jailed on charges of sedition as Editor of the Yugantar, the organ of the revolutionaries (1907). Released after eleven months, went to America (16.8.1908). Graduated from New York University (1912), post-graduation study of Sociology from Brown University. Visited Europe (1914) and Russia (121). Received D.Phil degree in Anthropology from Hamburg University (1923). Returned to India (1925) and led the movement of peasants and labourers. Died on 25.12.1961 in ancestral home on Gourmohan Mukherjee Street. First saw the Master at the age of 4/5 years at Ramchandra Datta’s Madhu Rai Street residence and subsequently at Cossipore (1886) where his mother appealed to the Master to send Narendranath home. Also accompanied mother to Kankurgachhi on 23.8.1886 for the internment ceremony of the Master’s relics there. Among his Bengali books the following are particularly noteworthy: Bharatiya Samaj Paddhati, Aprakashita Rajnaitik Itihas, Swami Vivekananda, Vaishnav Sahitye Samajtatwa. Of his English books the following deserve special mention: Swami Vivekananda, Dialectics of Hindu Ritualism (in two volumes), Swami Vivekananda: Patriot-prophet, a Study. Bhupendranath examined the mindset of the Master, Swamiji and subsequent monks of the Order and their work-style from a rigidly Marxist point of view.