The Caucasian Mountain Dog is a breed of large livestock guardian dog native to the countries of the Caucasus region, notably Georgia, Armenia, Azerbaijan, and Dagestan. Selective breeding of caucasian shepherds started in the Soviet Union from about 1920 from dogs of the Caucasus Mountains and the steppe regions of Southern Russia. The Caucasus Mountains in Georgia has historically been the most principal region of distribution of the Caucasian Mountain Dogs, both in terms of numbers and the quality of the dogs present in the area.