The Augustan Empire 43 BC

In any case, the new formula for Agrippa was only the first stage in a bigger reformulation, the 'constitutional settlement' of 23 в.с. On 1 July Augustus laid down his eleventh consulship, and must then have made it plain that in subsequent years he would not normally be a candidate for the office; for alternative formulae were adopted for giving him the various powers that he was relinquishing by giving up the consulship. But let us here be clear about the difference between powers and power. Augustus was not engaged in taking or declining or modifying the latter: factual power was not in question; he had that, totally, as long as he satisfied the general interest of governing class, plebs and armies. What was being taken or declined or modified was the expression of that power, which would settle expected boundaries of its use, of the behaviour of the ruler, and the scope to be allowed for a modus vivendi under his power. Not, then, retreats and compromises in a struggle over power, but in order to get the most acceptable modus vivendi. And in 23 the prime need was to restore to full availability the highest social prize of the aristocracy, the consulship,[188] which had been monopolized for years, as to one place, by Augustus, and twice also, as to the other, by Agrippa.⁷⁵ 'Business-as-usual' was what the aristocracy wanted as the price for their co-operation. Suetonius records, undated, a proposal by Augustus for there to be three consuls in any year when he was one, which was turned down:⁷⁶ the proposal tends to be associated with 19 B.C., but it might belong here in 2 3 - tried out, perhaps, on the senatorial steering committee and greeted with too much dismay. The alternative was for the ruler to relinquish the highest office.

Instead (or at least at the same time) Augustus received the grant, annually renewable but for life, of the official powers possessed by tribunes of the plebs, tribunicia potestas. We can argue that he needed the tribunician power so as, constitutionally, to be able to summon the Senate and to introduce legislation, and Augustus certainly so employed it. Some historians, regarding it as the principal cloak for autocracy, designate it as 'vague' and 'all-embracing': that is not right, for, unlike imperium, which was indeed vague, tribunicia potestas was a bundle of specifically defined powers.That is corroborated by the fact that an addition had to be made:[189] the Senate granted Augustus the right to make a formal motion at any session (a right that had not been part of the power of tribunes in the Republic). Tacitus looked in a different direction for the prime significance of the tribunician power: 'Augustus invented it as the title of highest pre-eminence, in order not to assume the name of king or dictator, and yet to have an appellation that would make him stand above all other imperii,[190] Tacitus thus saw it as a distinction rather than a power, and the same inference can be drawn from two other considerations, first that it came to be used as the chronological marker of the reign,[191] and, second, that it came to be the ultimate honour conferred on those chosen to be partners in the ruler's responsibilities - the sign of a 'colleague in rule', collega imperii. Also, of course, in an age attuned to symbols, tribunician power implied a relationship of protec­torate over the common people; though how far that impressed them is doubtful, and what they were hoping for was, as we shall see, something much more full-blooded.

The imperium of Augustus was redefined: it became imperium maius, which gave him prevailing authority over any other provincial governor in any case of conflict. It was, however, only proconsular imperium, giving him no authority in the home sphere such as he had possessed as consul (though, simply for practical convenience, he was allowed to have it 'once for all' in the sense of not having to drop it every time he entered the sacred pomerium of Rome and resume it every time he departed).⁸⁰ Some interpret the redefinition as compensating Augustus for the total maius imperium over the Roman world traditionally pos­sessed by consuls; but not all historians are agreed as to the reality, in practice, of the consular maius imperium, and, once again, not the least importance of the new device was to function as a distinction, keeping Augustus' imperium one stage higher than the new imperium of Agrippa.

'Constitutional settlement' is, then, too schematic a description of the changes of 23 B.C.; but it is only fair to add that the two elements, imperium proconsulate maius and tribunicia potestas, proved a very stable formula for the executive authority of Roman emperors for a long time to come.