The paper is devoted to establishing the circumstances and manner under which the Slav tribes and Vlachs in the southern Balkans were being integrated into the Byzantine system of provincial administration. Constantinople militarily imposed sovereignty on the settled Slavs, which was the first step towards their integration into the Byzantine state and society. When it comes to Vlachs, there was no use of military force. Special methods were applied to fit their autonomous organization into the frames oh the empire. In this regard, the paper compares the patterns of the integration processes of the two mentioned ethnic groups. [Projekat Ministarstva nauke Republike Srbije, br. 177032: Tradicija, inovacija i identitet u vizantijskom svetu]