Imperial Caesar, dead and turned to clay, Might stop a hole to keep the wind away.
The destruction of the Italian and western half of the old Roman empire was by the hands of northern barbarians who at first were mere conquerors and despoilers, but finally, affected by their contact with civilization and law, became residents in and rulers of Italy, and were proud to assume the titles and what they could of the dignity of Roman emperors. In the eighth century Charlemagne became substantially master of the western world, at least, and assumed the legionary eagle as he did the purple robes of an Augustus; and his successors held both with varying success until the tenth century, when German kings became supreme and in 962 founded that very unholy combination styled the Holy Roman Empire. For hundreds of years this fiction was maintained. At times its eagle indicated a real lordship over all Europe; between times the states broke apart, and, as each kept the royal standard, separate eagles contended for mastery. Thus Prussia and other German kingdoms retained on their shields the semblance of a “Roman” eagle; and the Teutonic Knights carried it on their savage expeditions of “evangelization” to the eastern Baltic lands.
All these were more or less conventional figures of the Bird of Jove in its natural form, but a heraldic figure with two heads turned, Janus like, in opposite directions, was soon to be revived in the region where, as we have seen, it had been familiar 2000 years before as the national emblem of the Eastern, or Byzantine, Empire, which for hundreds of years contested with Rome, both the political and the ecclesiastical hegemony of the world. Just when this symbol came into favor at Constantinople is unknown, but one authority says it did not appear before the tenth century. At that time the Eastern emperors were recovering lost provinces and extending their rule until it included all the civilized part of western Asia, Greece, Bulgaria, southern Italy, and much of the islands and shores of the Mediterranean; and they asserted religious supremacy, at least, over the rival European empire erected on Charlemagne’s foundation. It would seem natural that at this prosperous period, when Byzantium proudly claimed, if she did not really possess all “the glory that was Greece and the grandeur that was Rome,” such a double-headed device might be adopted, signifying that she had united the western power with her own. The evidence of this motive is doubtful, however, for it is not until a much later date that the figure begins to be seen on coins and textiles, first at Trebizond, particularly in connection with the emperor Theodore Lascaris, who reigned at the beginning of the 13th century. Dalton[25] suggests plausibly that this symbol may have become Byzantine through the circumstance that this Lascaris had previously been despot of Nicomedia, in which province Bogaz-Keui and other Hittite remains were situated, and where the bicephalous carvings heretofore alluded to are still to be seen on rockfaces and ruins, always in association with royalty.