The Tibetan Mastiff's Origins and History Source: Wikipedia Country/Region of Origin: Tibet Original purpose: herding, guarding Name: also known as Do-Khyi. Historical notes: Tibetan Mastiff dogs belong to an ancient stock. It is believed that at least most of all mastiffs descend from that old Tibetan stock. They were once used to guard the holy city of Lhasa and even now those few that remain in Tibet still make excellent guard dogs for ferocity and aggression. The breed began to die out in Tibet during the 19th century until English breeders took it home and propagated it. Even now they are still rare.