It followed naturally that the exarch, who resided at Ravenna, had at his court, besides an officium befitting his rank, a number of advisers and assistants for the miscellaneous branches of his activity. We will only mention here the consiliarius, the cancellarius, the maior domus, the scholastici versed in jurisprudence, and in Africa a ὑποστράτηγος with the rank of patricius, a representative of the emperor’s representative. He was further, like all generals of that time, surrounded by a number of private soldiers, gentlemen-at-arms who held a more distinguished position than soldiers of the regular army. The court of these vice-emperors was in every aspect a copy of the imperial court, and their powerful position makes it conceivable that, when in the middle of the seventh century the centre of the Empire was in distress, the attempt was repeatedly made both from Africa and Italy to replace the emperor by an exarch. It was in this manner that the dynasty of Heraclius attained to the throne.
The consequences of the uninterrupted state of war, caused in Africa by the Berbers and later by the Muslims, and in Italy by the Lombards, of course affected, not only the head of the general administration, but also its organisation and its efficacy. Tripolitana was detached from Africa, probably under the Emperor Maurice, and added to Egypt. Mauretania Sitifensis and the few stations of the Caesariensis which the Empire was able to uphold, were joined together into one province, Mauretania Prima, whilst distant Septum, with the remains of the Byzantine possessions in Spain, became the province Mauretania Secunda. Of still greater importance is the fact that Justinian’s plan of restoring the frontiers of the Empire to the extent they had before the Vandal occupation, was never carried out. It even became necessary in several provinces to move back again the line of defence already reached, so that the duces did not hold command in the border-lands of their own provinces, but were stationed with their garrisoned legions in the interior. This makes it impossible to define the sphere of local power between the dux and the tribuni on the one hand, and the praeses on the other. The provinces themselves became as it were limites. Just as the praefect continued to exist under the exarch, so there existed, at least in the beginning of the seventh century and perhaps even up to the definite loss of Africa, side by side with the duces, a number of civil praesides, not to speak of the various revenue officers who were employed for the taxation. Naturally the duces and the tribuni who were appointed by the exarch proved the stronger, and continually extended their powers at the expense of the civil officials. The development, which must have led to the complete suppression of the civil administration, hardly reached its final stage in Africa, because it was forcibly cut short by the Mahometan occupation. It went further in Italy. The Lombards in their onslaught had broken up the whole of the Italian administration in the course of about ten years; attempts to re-establish it failed, and when about the
