ABSTRACT
A long tradition, extending back to the origins of the Christian Empire and even further, led the Byzantines of the Middle Ages to conceive of their foreign policy on two different levels: that of reality and that of historiosophical doctrine. The remarkable text is in conformity with the basic ideas of the Christian Empire and only extends the principles established in the time of Eusebius and faithfully maintained in Constantinople through the centuries to the medieval Byzantine doctrine of the 'family of princes'. The parallelism goes very far, and it is immediately apparent that this image could not have been invented until late, and in a milieu like Byzantium where the principle of the single Christian monarchy remained unshaken. As Sovereign of the World, the Emperor holds a monopoly of the divine grace reserved to the supreme power on earth.
