Namasudra, also known as Namassej or Namassut, is an Indian avarna community originating from certain regions of Bengal, India. The community was earlier known as Chandala or Chandal, a term usually considered as a slur. They were traditionally engaged in cultivation and as boatmen. They lived outside the four-tier ritual varna system and thus were outcastes 
Joya Chatterji mentions that "in the 1870s, Chandals of Bakarganj and Faridpur boycotted caste Hindus "when they refused to accept an invitation to dine from a Chandal headman; and henceforth they "battled continuously to improve their ritual position" and later claimed the "more respectable title of 'Namasudra' and Brahmin status". According to one section of historians, the Namasudras were a "large non-Aryan caste of eastern Bengal, mainly engaged in boating and cultivation". However, Niharranjan Ray, a historian, believed that they have a closer relation with north Indian Brahmins, saying "they are of the same line as the Brahmans of north India; indeed there is a closer relation between the north Indian Brahmans and the Bengali Namahsudras than between the north Indian Brahmans and the Bengali Brahmans, Kayasthas and Vaidyas." Again, according to the observations of T.C. Raychaudhuri, there is minor trace of "pre-Dravidian or Nisadic element among the Bagdis and Namasudras" along with "good percentage of Dravidian element".
From the late 1930s, attempts by the Namasudras of Bengal Presidency, British India, to improve the way in which society perceived them received support from the bhadralok (an influential class). The bhadralok, to increase their own power in Bengal, sought to enlarge their political base by bringing the Namasudras into a united Hindu political community.
Sekhar Bandyopadhyay mentions that the Dalit of Bengal became involved in the Partition related movement, and the "two most important communities, who dominated dalit politics in the province, were the Namasudras and the Rajbanshis". Bandyopadhyay also mentions that the Namasudras, earlier known as the Chandals, who mostly inhabited the districts of East Bengal, were forced to migrate to West Bengal during the Partition of India in 1947.
The Namassej Samaj Andolon is a socio-political organisation that claims to represent the community.
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