It represents the study of the generic composition of the Yakuts in the system of administrative organization of Yakutia in XVII–XIX centuries. The largest townships in Yakutia in the XVIII century were established territorial units – called “ulus”. Six central Yakutia ulus framed Yakut ethnic group, as they walked out of migration in different directions of the vast region. Genealogy ancestors were raised in central ulus, so called the sons of the Yakut people Elleya and Omogoya grandparents. In addition to the six main Yakut ulus, the great importance in the formation of this people were such ethnonyms as Tumat, Bethune and Bootulu occurring in the Vilyui in the North. Settling Yakut birth to the Northeast of Siberia, people from the central areas, has emerged in the Vilyui and northern groups of Yakut. At the same time, this was a process of assimilation of many Tungus clans. The study of the Yakut ulus (district) reflects the development of the vast expanses of the Yakuts to the Northeast Asia, assimilation Tungus and Yukagir birth. The article traces the process of the formation and propagation of the Yakut childbirth over a vast territory of Yakutia and adjacent areas. The Yakut labor migration of its metropolitan – Central Yakutia, Vilyuisky and northern areas has led to their colonies in the outskirts. The development of regions with different geographical landscape: taiga, tundra, mountain, lake areas and river valleys, along with busy hunting and fishing, has led to the spread of cattle and hay to the Far North. This contributed to the emergence of the ethnic Yakuts groups who called the Tungus.