The monograph is an attempt to explore the history of inter-princely relations in Russia in the 40-70s of the X century on the basis of the circle of sources available today. The author's desire to find out what role two dozen noble Rus who participated in the conclusion of the treaty of Rus with Byzantium in 944 played in the political life of Rus, led him to original conclusions about the political structure of Kievan Rus of the 10th century as a whole.