The Title of Russian Princes “Khagan” in Sources and Historiography

The article is devoted to the problems of interpreting the chronologically first mention of the Khagan of the Rus, which is found in the Annals of St. Bertin in connection with the reception of the embassy of the Rus at the court of the Frankish emperor in 839. Discussion of this message in the context of mentions of the Rus and their ruler in other sources close in time allows us to assume, firstly, that Lat. “rex illorum chacanus vocabulo” of the Annals of St. Bertin is a standard formula for many medieval sources for transferring the title of a foreign ruler, and secondly, that the appearance of the Russian embassy first in Constantinople and then in Ingelheim was not an intermediary mission undertaken in the interests of the Khazar Khagan, but an attempt to develop the Rus’ own relations with Byzantium, an attempt to politically formalize their trade and economic activities on the territory of the empire, which, in turn, makes us believe that in 839 the title of “Khagan” referred specifically to the ruler of the Rus’, and not to some other ruler.