Baidya or Vaidya is a Hindu caste community of Bengal. In pre-colonial history of Bengal, Baidyas were regarded as the highest Hindu castes along with Brahmins and Kayasthas in the caste system of Bengal.
Baidya is a caste community confined to Bengal, which has traditionally claimed Brahmin status, but has been most commonly associated with the Ambashtha caste or sub-caste. Ambashthas are believed to have originated from Brahmin father and Vaishya mother, and variously thought to be a sub-caste or a separate caste or even technically belonging to the Brahmin varna. Historian Bijay Chandra Mazumdar strongly suggests that the Vaidyas of Bengal owe their origin to the Vellala Vaidyas, known for their military prowess in Southern India, who actually started functioning as Brahmins some time earlier than 10th century AD, and originally got the designation 'Vaidya' on account of their knowledge or rather the study of the Vedas. The Vellala Vaidyas also serverd as military leaders and high civil officers apart from being priests of the Dravidian Kings. It is believed that these migrants, probably Ambashthas as well as the other groups like Vellala Vaidyas, started moving from north and south to Bengal during the Pala Empire. They mainly dealt with medicine and other fields of study. In the later half, some of them rose to power and endeavored to revive Vedic Hinduism in predominantly Buddhist Bengal. Kulagranthas of Rarhiya and Varendra Brahmins and Vaidyas (for example, Dhananjay's 'Kulapradip', Bharat Mallik's 'Chandraprabha', Ramananda Sharma, Ananda Bhatta) say that Sena Kings were Vaidyas/Ambashthas of Vaishwanar gotra. Most of the Baidyas perform rituals like wearing the sacred thread. It is believed that legendary Sena King Ballal Sen divided the Baidyas into two divisions, wearing the sacred thread was compulsory for one group, but optional for the other. Tej Ram Sharma, an Indian historian, says that
Originally the professions of Kayastha (scribe) and Vaidya (physician) were not restricted and could be followed by people of different varnas including the brahmanas. So there is every probability that a number of brahmana families were mixed up with members of other varnas in forming the present Kayastha and Vaidya communities of Bengal.
During historical times, Brahmin, Baidya and Kayastha together formed the next elite group apart from rulers, in the power structure and all the rulers of Bengal - Palas, Senas, Pathans and Mughals, had to rely on their support. Baidyas shared the knowledge of Sanskrit with Brahmins. These three castes held major landholding and control over education and major professions.
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