the nashyas trace their origin to the indigenous communities of koch rajbongshi of northern west bengal, though some of them are also from mech community. there conversion to islam is said to have taken over two to three centuries, and the nashya still retain many cultural traits of their pre-islamic past. most people of the community are non-practicing muslims though the newer generations are becoming increasing islamic due to globalization. from historic evidence, it seems a segment of the indigenous population of north bengal converted started to convert to islam when the region fell under the control of bakhtiyar khilji. some of the earliest converts were the chiefs ali mach and kala pahar. tradition also ascribes the conversion of several lineages to sufi saints such as torsa pir, pagla pir, shah fakir sahib and shah gari sahib.