The objective of the research presented in the book is to determine the forms and composition of the elite of ancient Russian society in the 10th–11th centuries, especially that part of it that participated in the most important military and political decisions. The data from the most ancient chronicles, treaties between Rus' and Byzantium in the 10th century, “Russian Truth” and other sources are analyzed from a broad comparative historical perspective. The groups that in the 11th century are described in detail. constituted the most important elements of the elite of Rus' - the nobility (boyars) and the military servants of the princes (youths or grid).