Gibbon's statements here require correction, though the question of the exact constitution of the power of the princeps is still a matter of debate.
Augustus at first intended to found the principate as a continuation of the proconsular imperium with the consulate, and he held the consulate from 27 to 23 b.c. But then he changed his mind, as this arrangement gave rise to some difficulties, and replaced the consular power by the tribunitian power, which had been conferred on him for life in 36 b.c., after his victory over Sextus Pompeius. Thus the principate depended on the association of the proconsular with the tribunitian power; and Augustus dated the years of his reign from 23, not from 27 b.c. After this he filled the consulship only in those years in which he instituted a census.
(5) P. 65.—"Supreme pontiff."
He became Pontiff in 12 b.c. Besides being Pont. Max. Augustus belonged to the other sacerdotal colleges. He was augur, septemvir, quindecimvir.
11. THE CONSTITUTIONAL SIGNIFICANCE OF THE PRINCIPATE OF SEPTIMIUS SEVERUS—(Pp. 120-125)
The name of Septimius Severus marks an important stage in the development of the Principate of Augustus into the absolute monarchy of Diocletian. If he had been followed by emperors as strong and far-sighted as himself, the goal would have been reached sooner; and, moreover, the tendencies of his policy would have been clearer to us. But the administration of his immediate successors was arbitrary; and the reaction under Alexander threw things back. Severus had no Tiberius or Constantine to follow him; and like Augustus he committed the error of founding a dynasty. His example was a warning to Diocletian.
The records of his reign show that he took little account of the senate, and made much of the army. This has been brought out by Gibbon. But it would be a mistake to call his rule a military despotism. He did not apply military methods to civil affairs. He was more than a mere soldier-emperor; he was a considerable statesman.
His influence on constitutional history concerns three important points. (1) He furthered in a very marked way the tendency, already manifest early in the second century, to remove the line of distinction between Italy and the provinces. (a) He recruited the Prætorian guards, hitherto Italians, from the legionaries, and so from the provinces. (b) He encroached on the privileges of Italy by quartering one of three new legions, which he created, in a camp on Mount Alba near Rome. (c) He assumed the proconsular title in Italy. (d) By the bestowal of ius Italicum he elevated a great many provincial cities (in Dacia, Africa, and Syria) to a level with Italy. (2) He increased the importance of the Prætorian Prefect. We can now see this post undergoing a curious change from a military into a civil office. Held by Papinian, it seemed to be the summit in the career not of a soldier but of a jurist. (3) The financial policy of Severus in keeping the res privata of the princeps distinct from his fiscus,—crown property as distinguished from state revenue (cp. p. 99, footnote 52).
There is no doubt that the tendency to give effect to the maius imperium of the princeps in controlling the governors of the senatorial provinces and the republican magistrates (consuls) was confirmed and furthered under Severus. For example, governors of senatorial provinces are brought before his court, Hist. Aug. x. 4, 8. The maius imperium, used with reserve by the earlier emperors, was one of the chief constitutional instruments by which the princeps ousted the senate from the government and converted the "dyarchy" into a monarchy.
Note.—In regard to the prefecture of the Prætorian guards, the rule that it should be held by two colleagues was generally observed from Augustus to Diocletian. We can quote cases of (1) two prefects under Augustus, Tiberius, Gaius, Claudius, Nero, Otho, Vitellius, Domitian, Trajan, Hadrian, Pius, Marcus, Commodus, Julianus, Severus, Caracalla, Elagabalus, Macrinus, Alexander,
