a practice that appears to have been initiated by the Emperor Claudius (r. 41–54); so, in the late Empire individuals could be raised to the clarissimate by an imperial codicillus clarissimatus (diploma of clarissimate status), and the title could be extended to the holders of an ever-increasing number of hitherto equestrian state posts. (See CTh XII.74.5 (371); Cassiodorus Variae 6.14.)
Clarissimi became senators proper in the traditional way, namely by holding one or other of the republican magistracies, and it was still normal practice for young nobles to become senators unless too poor to be able to afford the expenditure which the tenure of a republican magistracy now entailed. Membership of the Senate was no longer of any practical significance because the Senate as an institution was powerless, and it is hardly surprising that its meetings were so unattractive to its members that the quorum had to be fixed at fifty. (Symm. Or. VI.)
Under the tetrarchy, the senatorial order formed a reasonably homogeneous group comprising men of senatorial birth, since, in the latter part of the third century, praetorian prefects were evidently the only novi homines to join its ranks. When, however, the senatorial cursus honorum (“career”), which Diocletian had turned into a cul-de-sac, became once again an important avenue of advancement under Constantine and his successors, this homogeneity came to an end. For now, in addition to men of senatorial birth, the order was flooded with office-holders whose positions had given them the clarissimate automatically and, as the fourth century passed, more and more offices came to carry senatorial rank with them.
This influx of new men into the clarissimate eventually reduced its significance, and as a result, office-holders in the upper echelons of power began to differentiate themselves from ordinary clarissimi, by adding to their titles spectabilis (notable) in the case of vicars and proconsuls and those equated with them in rank in the military and court hierarchies and illustris (illustrious) in the case of the praetorian and urban prefects, magistri militum (generals), and the major palatine officials. These new titles were not hereditary, and the son of an illustris would be a mere clarissimus until he earned a higher title through office. (See CTh 16.5.52 412.)
In the pre-Constantinian era, therefore, titles are much more precise indices of a man’s social background than they are in the period from Constantine onward. The equestrian titles egregius and perfectissimus are, of course, always signs of non-senatorial birth, but the gradual increase during the fourth century in the number of posts carrying with them an automatic clarissimate made the equestrian titles obsolete and gave many men of non-senatorial origin the same title as that of the nobles. Thus, while under the tetrarchy, the clarissmate alone is sufficient evidence of nobility (except in the case of praetorian prefects)later, especially in the post-Constantinian period, it usually throws no light on a man’s origins, and other criteria of nobility must be employed.
In the case of low-ranking governors such as praesides, however, the title clarissimus is a pointer to senatorial origin. Up to at least 379, the normal title for a praeses was perfectissimus, and any praesides who were clarissimi may be assumed to have been of senatorial origin, as it is inconceivable that the emperor would elevate a novus homo to senatorial rank just to appoint him a praeses, a position which he could and indeed should hold as an equestrian. In fact, the only datable cases known of praesides with the clarissimate under Diocletian were three praesides of Syria.
Emperor and Senatorial Aristocracy
In the three centuries before Constantine, the senatorial aristocracy had steadily been losing political power and influence. Conscious that imperial power and senatorial power were at opposite ends of a political see-saw, emperor after emperor encroached on the power of the Senate from the early Principate onward until it was left with only ceremonial functions. But though the Senate as an institution was no longer of any account, the men who comprised it continued to have a monopoly of most of the high state posts, notably provincial governorships.
In the Principate, the emperor controlled recruitment to the Senate, and the continued ascendancy of senators in government, particularly as provincial governors, and the hereditary nature of senatorial rank perpetuated the old Republican ethos. Once a man became a senator he was marked off by title, dress, and office alike from lesser mortals and from his own past life. Despite, therefore, the impotence of the Senate as a body, there was an imperial senatorial aristocracy with an esprit de corps. This aristocracy was very different, of course, from the self-perpetuating aristocracy of the Republic. Indeed, especially from the reign of Claudius (41–54), the huge bronze portals of the curia were continually welcoming new members from an ever- widening circle of provinces. New men rubbed shoulders with scions of ancient families and gradually became assimilated to the senatorial ethos. Yet at no time would the newcomers have outnumbered the more established elements, and not a few office-holders even in the third century could trace their senatorial rank back for a century or more. (Arnheim 1972, p. 32.) Among the surviving senatorial families in the third century were some ancient Republican lines, such as the Acilii Glabriones, Valerii Messallae, and even possibly the Cornelii Scipiones.
By the third century, the Senate as an institution had no power worth mentioning. Yet it was from this body, whose esprit de corps stemmed from a combination of heredity and assimilation, that the chief office-holders of the empire continued to be drawn.
At first, emperors worked through the Senate, subverting the position of the older families by introducing their own nominees into the Senate and then appointing them to governorships, thus keeping within the traditional constitutional framework.
In the course of the third century, however, this traditional framework was abandoned. Emperors, it is true, had always been able to appoint men of non-senatorial origin to high posts by introducing them into the Senate beforehand. But in the third century, there was a growing tendency to bypass the Senate by appointing non-senators directly to governorships without bothering to make them senators.
There already were precedents in the early Principate for the appointment of non-senators to high state posts. The positions of praetorian prefect and prefect of Egypt are cases in point, as are the governorships of Mauretania, Thrace, Judea, Raetia and Noricum, and smaller areas such as the Cottian and Maritime Alps and the Balearic Islands. All these provincial governorships, it is worth noting, were new posts, as emperors tended to be loath to break with tradition in any radical way.
However, in the latter half of the third century, emperors developed an appetite for appointing equestrians directly to governorships. By the end of the century, not only were most governorships open to equestrians, but they were also closed to senators.
A passage in Aurelius Victor has given rise to the belief that it was an edict issued by Gallienus (r. 253–268) that was instrumental in depriving senators of military commands. Because of the somewhat ambiguous phrasing of the passage in question, it has become the plaything of scholars. (Arnheim 1972, p. 34 ff.) There is, however, some evidence of senatorial governors exercising specifically military functions after the date of the supposed edict, for example, M. Aurelius Valentinianus in 283. (CIL.4102-03.) So, Aurelius Victor may well have been telescoping into a single “edict” a protracted development. For, there can be no doubt that there was a growing tendency in the period from Gallienus onward to appoint non-senatorial governors directly.
Among the proconsuls of Africa are to be found some of the noblest names of the age: T. Flavius Postumius Titianus, Amnius Anicius Iulianus, C. Annius Anullinus, Ceionius Rufius Volusianus. (See PLRE–Fasti.) The origins of these men contrast rather markedly with those of the governors, all praesides, of the new African and Asian provinces. The only praeses of Byzacena of known origin under the tetrarchy, (….) Junius Flavianus, was a perfectissimus. (ILAlg. I.3832.) In Tripolitana, two such praesides are known: C. Valerius Vivianus Obsequius and Aurelius Quintianus. Both of these were
