without restriction, both in their military and in their civil capacity, subject only to the instructions they received from the Emperor. Procopius calls each alike αὐτοκράτωρ τοῦ πολέμου.
Circumstances, however, allowed neither country any lasting peace; martial law continued as a consequence of the state of war, and neither Africa nor Italy could safely be left without an active army. It became necessary to create and to uphold a supreme authority, to which the civil administration had to be subordinated for military purposes. In Africa a passing attempt was made by Justinian to equip the praefectus praetorio with the power of a magister militum, but this was an exceptional case. In Africa, as also in Italy, when the Lombards invaded it after the recall of Narses, the rule was to appoint extraordinary military commanders, who held a high rank and were superior to the praefectus. But when the state of war proved to be chronic, the extraordinary office developed into a regular one. In the year 584 an exarch is mentioned in Italy for the first time, and here as in Africa the title exarch is henceforth commonly applied to the head of the military and civil administration. In this combination of military and civil functions the exarch reminds us of certain exalted provincial governors, whom Justinian, deviating from the general principles of the Roman administration, had already installed in the East. But the exarch is far more than these. Holding, as he does, the highest office in his division of the Empire, he not only belongs to the highest class with the title excellentissimus, but he owns also the full title of patricius, a distinction not usually shared by the praefect. If the patrician holds a court office it is usual, in official language, to substitute this for the title patricius, as for instance cubicularius et exarchus, or occasionally patricius et exarchus. In ordinary life, when speaking of the exarch in Italy and Africa, only the title patricius was used.
The power of the exarch was practically unlimited. Like the Gothic kings, he was the emperor's representative; and as such, like his predecessors, e.g. Belisarius and Narses, he held absolute command over the active troops temporarily stationed in that part of the Empire, as well as over the frontier legions. At the same time he took a hand, whenever it pleased him, in the civil administration, decided ecclesiastical matters, negotiated with foreign countries, and concluded armistices. His power was only limited in time, inasmuch as he might at any moment be recalled by the emperor, and in extent inasmuch as his mandate applied only to a definite part of the Empire. He could therefore issue decrees, but could neither make laws nor conclude a peace valid for the whole of the Empire. The command of the exarch of Italy extended beyond Italy to the rest of the old dioecesis of West Illyricum, and to Dalmatia, which also, since Odovacar's time, had been added to the Italian kingdom. The military system of Sicily, on the other hand, was allowed, at least in later years, to develop independently.
