Sen, Sen-Sharma, Sengupta (Sen-Gupta), Dasgupta, Duttagupta, Gupta, etc. belong to the Baidya/ Baidhya / Vaidya / Vaidhya community, a Hindu upper class caste (literally means a physician as well as a vedic scholar in Bengali/Sanskrit).This originally Brahmin caste [with mostly Yajurvedi Kanva-Shakha Saraswat heritage] had formed a separate cluster due to some technicalities of their profession (largely due to the handling of the sick and dead as traditional doctors) and due to some historical events during Lakshman Sen's rule. This group is found largely in Bengal. Kulagranthas of Rarhiya,Barendra and Vaidya brahmins say [e.g.- Dhananjay's "Kulapradip", Bharat mallik's "chandraprabha", Ramananda Sharma, Ananda Bhatta] that Sen kings were Vaidyas/Ambastha of Vaishwanar gotra. Ambastha was the name of a place in northwestern India where many vaidyas resided and hence came to be known as Ambastha-brahmins. They started to migrate from north and south to Bengal during the Pal empire. They mainly dealt with medicine and other fields of study . In the later half some of them rose to power and endeavoured to revive Vedic Hinduism in a Budhhist-predominant Bengal. In old sanskrti texts written by kulacharyas like Chaturbhuj, Nulo panchanan etc., it is written that king Shalvan, king Adishur were born in Vaidya families. Adishur brought newer waves of Brahmins in Bengal from kannauj including 4 more Vaidya pandits of Dhanvantari, Shaktri, Kashyap and Moudgalya gotra. 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 other Brahmins. These three castes held major landholding and control over education and major professions.