 They are considered to be the descendants of the Samoyedic and Ugrian peoples of the West Siberian Plain – the Nenets, Khanty and Mansi – who adopted Siberian Tatar language and converted to Islam, while also preserving some elements of their traditional beliefs.Their traditional areas of settlement are separated from Tobolsk, the Russian and Siberian Tatar settlements by Irtysh River, by impassable swamps which is the reason for their name in the Russian language (literally, "Tatars who live behind the swamps").This separation also helped them to preserve some elements of their traditional culture, which has been lost by other Siberian groups.