According to the data of 2008, eight horsemen buried in grave pits with complete horse skeletons had been discovered in only four of the East Lithuanian barrow cemeteries of the second half of the fifth century. The majority of these graves already were pillaged in antiquity. The barrows with graves of men interred with horses are concentrated in a small territory between Lakes Tauragnas, Žeimenis, and Vajuonis, in an area that does not exceed 50-60 sq. km. Particularly rich burials with silver and silver artefacts, most of which originated in the middle Danube and Carpathian Basin, are found in this small region. Such burials are associated with supreme rulers and high ranking military leaders. Burials of well, but standardly armed, horsemen and infantrymen also are found in the region. They can be associated with the retinue of supreme rulers. Current data suggest that while multi-ethnic groups of people reached the East Lithuanian micro-region between Lakes Tauragnas, Žeimenis, and Vajuonis during the Migration Period, the newcomers vanished from the local population over the course of four generations. This small region’s concentration of great wealth and military power, along with marked differences in social structure emphasized even in the structure of the barrow cemeteries, would suggest that a form of government identical to that of a chiefdom had been created in the region.