The formation of a tribal group of Kalmak in the Bashkir estate groups is considered. The author critically assesses the arguments given in the works of B. A. Aznabayev on the issue under consideration. Attention is paid to the problems of estate organization of society. The results of comparative analysis of archival materials and published sources relating to the formation and early history of the group of ayukinskie Kalmyks in the Southern Trans-Urals in 18th century are presented. The question of the role of the state in the creation of the Sart-Kalmak volost, as well as in creating conditions for the formation and preservation of the Kalmak tribal group is raised. Particular attention is paid to the definition of the social status of the yasak population as a class, whose duty was to pay yasak, and whose right (privilege) was the patrimonial right to land from which yasak was paid. The novelty of the study is seen in the fact that for the first time the archival documents concerning the decision on the land allotment to the groups of ayukin Kalmyks, serving Sarts and serving meshcheryaki were put into circulation in 1748, clearly showing the decisive role of the state in determining the social status and land rights of these groups of the population. The relevance of the study is determined by the relentless interest in ethnic history and rather contradictory interpretations of socio-cultural processes in the Southern Trans-Urals of the 18th century in the works of the opponent.