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Bihari Mauritians are descendants of predominantly Bhojpuri-speaking migrants from Bihar who moved to Mauritius. A majority of Indo-Mauritians are of Bihari origin, and most Mauritians are Indo-Mauritian. Caste-wise, many Bihari Mauritians are Vaishyas, with notable groups including Bhumihars, Brahmins, Rajputs, Koeri, Chamars, Yadav, Kurmis, Banias, and Kayastha. Except for one, all Mauritian Prime Ministers have been of Bihari Vaishya descent.
The community includes a Hindu majority with a Muslim minority. About 65.7 % of the 1.3 million population of Mauritius is of Indian origin, most of them from Bihar state, with Bhojpuri as their ancestral tongue.
Bihari Mauritians primarily originated from the Gaya, Chhapra, Bhojpur, Gopalganj, and East and West Champaran districts. During the early period of migration, the laborers referred to Mauritius as "Marich." Amitav Ghosh's novel, Sea of Poppies, is set in this era and depicts the plight of impoverished Bihari migrants who undertook journeys to Mauritius and other distant colonies of the empire.
Social stratification
Though the island is divided on ethnic and religious grounds, 'Hindu' Mauritians follow a number of original custom and tradition, quite different from those seen in the Indian subcontinent. The Indian Brahminical caste structure is based on the varna system, which categorizes society into four main groups: Brahmins, Kshatriyas, Vaishyas, and Shudras. Within this system, Brahmins (referred to as Maraz), Kshatriyas (referred to as Babujee), and Vaishyas (referred to as Vaish) are classified as "grand nasyon" or high castes. These groups correspond to the Hindu concept of dvija, or "twice-born." In contrast, all other castes are classified as Shudras, also known as "ti nasyon" or low castes, which include groups such as Ravived and Rajputs. This classification can apply to individuals, neighborhoods, or shrines. In certain contexts, Vaishyas may also be regarded as intermediary castes.
Bates, Crispin (2016). Community, Empire and Migration: South Asians in Diaspora. Springer. p. 14. ISBN978-0333977293. Retrieved 2020-07-01.Some 'castes' in Mauritius in particular are quite unrecognizable from a subcontinental perspective, and may incorporate mutually antagonistic castes from an Indian setting into a single group. A 'Rajput' in Mauritius is of a Shudra caste, the title having been usurped by this group in the nineteenth century. Ethnolinguistic distinctions differentiate Bhojpuri/Hindi speakers from Tamil, Telugu speakers and Marathi speakers despite all being Hindus they maintain certain regional endogamy. Even Gujarati speakers are seen as a separate community, from a trading rather than an indenture background, and maintain a social distance from descendants of 'coolies'. The former Brahmin elite are referred to as the 'Maraz' and together with the former Rajputs and other Kshatriyas, now called 'Babujis', enjoy the prestige conferred by high-caste status, whilst politically they complain of marginalization.
Hinduism (majority), 
Islam (minority)
Indian diaspora