Bergjuden
In the year 1888 A. Sh. Anisimov showed the closeness of the language of the Mountain Jews and the Tats. In his work "Caucasian Jews-Mountaineers" he came to the conclusion that the Mountain Jews were representatives of the Iranian family of the Tats, which had adopted Judaism in Iran and later moved to the South Caucasus. The ideas of Anisimov were supported during the Soviet period: the popularization of the idea of the Mountain Jews' Tat origin started in the 1930s. Through the efforts of several Mountain Jews, closely connected with the regime, the idea of mountain Jews being not really Jews at all but Judaized Tats became widely spread. Some Mountain Jews started to register themselves as Tats because of secret pressure from the authorities.