The later empire is often called the dominate as opposed to the principate of the early emperors. For the increased autocracy of the times, no longer concealed under the ingratiating Republican term of first citizen (princeps), was now brought out into the open in a new, undisguised presentation which may be symbolised by the title dominus or Lord. This form of address, used by slaves to their masters, was for a long time shunned by rulers who cared for public opinion. Gradually, however, it came to be applied to second-century monarchs in unofficial language and in the administrative terminology of the provinces. This practice was not at first followed by the central government, but Septimius was called Lord, or Our Lord, with greater frequency than his predecessors. It was characteristic of the third century to give official sanction to usages and titles that had hitherto been informal, and by the time of Severus Alexander the emperor was being called Lord on many inscriptions – though the Historia Augusta, at pains to emphasise his moderation, claims that he would not allow himself to be addressed in this way. But then Aurelian, at Serdica (Sofia) in his own home country, was described on a coin as ‘born god and lord’ (DEO ET DOMINO NATO). This remained exceptional; but the official coinage, habitually conservative about titles, extended the use of the word dominus to Diocletian and Maximian, though not until after their abdication (305). Licinius and Constantine, during their joint reign, seem to have been the first to bear the title officially.1
One of the Augustan fictions, then, had been dropped. But the dropping of slogans was never complete. Marcus Aurelius, while raising funds for his German wars, had declared that he himself possessed nothing and was lodged by the state. This was a corollary of the Stoic view that a ruler was there to serve his subjects. The writings of Constantine, too, are full of references to his service and his mission. Throughout the period the two theories of autocracy and service coexisted, and were complementary to one another rather than contradictory. This parallel, simultaneous existence of two approaches to the imperial role was reflected by jurists. There was a longstanding tradition that the emperor was subject to the laws, and this interpretation continued to be expressed. But the situation was complicated by his role as creator of law (p. 78). The jurist Gaius, in the second century, had already recognised the full validity of imperial enactments, and in the Severan age Ulpian corroborated this.2 Conservatives, such as the historian Dio Cassius, might express hopes that the senate would still legislate, but by the end of the second century its lawgiving activities were superseded, just as those of the national assembly had become obsolete two hundred years earlier.
Did the fact that the emperor had now become the one and only legislator mean that he himself was above the laws? His predecessors never had been, and emperors themselves continued to assert that they were bound by law. One of the outstanding jurists of the time, Paulus, takes the constitutionalist view that it is ‘befitting to the imperial majesty to live according to the laws from which the emperor himself seems to be exempt’.3 Ulpian, on the other hand, was conscious of cases in which the emperor’s exemption was real and absolute.4 Paulus’ formula of constitutional monarchy may perhaps represent a reaction, under the correct young Severus Alexander, from the more autocratic version (departing from the principate of Augustus), that Ulpian had sponsored under Caracalla. But it was Ulpian’s formulisation which stood for the future in which it became possible to address a fourth century emperor as ‘the living law and superior to written laws’. And this was generally acceptable, since anarchy and invasion had bred everywhere a passionate longing to be looked after by a superior being.
And yet, by a paradox, the only way in which the emperor could exercise this supremacy, and protect his people, was by a division of responsibility. The problems were too great for one man to deal with alone. Nor was it enough to delegate to the praetorian prefect the powers of a deputy (p. 76); he lacked the charisma, and was often rightly suspected of seeking to become emperor himself. For a spreading of the load which would not cause such anxieties it was necessary to turn to other members of the imperial family itself. From the time of Augustus onwards, sons and adoptive sons had been elevated to preferential status during the ruler’s lifetime (p. 14). Marcus Aurelius and Lucius Verus reigned conjointly with equal rights and sometimes an informal territorial division (161–9), and then it was said that Caracalla and Geta, joint rulers as a result of the strong dynastic policy of their father Septimius, proposed to share out the empire by a geographical partition (211).5 This is doubtful (and in any case Caracalla murdered Geta), but it represents the practice which soon developed as the best means of administering the empire, defending its frontiers, and keeping a closer watch on possible rivals and usurpers. Moreover, such measures could be commended by antiquarians – who were numerous in governing circles –through comparison with the ancient institution of the two consuls, serving together as colleagues. Later, it was with that antique practice in mind that the senate briefly and disastrously elevated two of its senior members, Balbinus and Pupienus, to joint imperial status, with the former to rule at home while the latter took the field against Maximums I (238). This association was signalised on the coinage by untruthful references to ‘the Mutual Love of the Emperors’. Then the hard-pressed Valerian divided the empire into two parts, taking the east himself, and giving the west to his son Gallienus (256). This was the first overt territorial division,6 though it did not lessen the father’s authority; the same was true when Carus left his son Carinus in charge of half the empire (282–3).
After Carus’ death, Carinus divided the empire with his brother Numerian. But it remained for Diocletian to regularise the division, with himself remaining in the east and his fellow-Augustus Maximian in the west. Moreover, this was not a twofold but a fourfold division, with not only two Augusti but also in due course two Caesars (Constantius I Chlorus and Galerius) – each under one of the Augusti, and all four of them with a geographical region of their own. This situation was partly the product of necessity, for Maximian could not have lower rank than the British usurper Carausius against whom he or his subordinate was fighting (p. 17), and the two Caesars were likewise elevated under duress of outside events. But the arrangement was developed into a system which was intended to be permanent. This Tetrarchy multiplied authority, but did not divide it; in spite of the regional subdivisions, the empire was still ‘an undivided patrimony’.7 The law of the one Augustus was the law of the other, and Caesars obeyed both Augusti, and legislation was in the name of all four.
After ruling for twenty-one years, Diocletian abdicated, though whether he did so by a long prearranged plan or owing to coercion and physical collapse will never be known. The simultaneous abdication of his colleague Maximian was reluctant and temporary, and the system of neat transitions and promotions, which had only held together owing to the force of Diocletian’s personality, broke down. Within the next two decades Constantine managed to re-establish unity, and yet he too, looking into the future, finally thought it best to ordain partition among his three sons and another young kinsman. By the end of the fourth century the dichotomy between eastern and western empires was permanent, and In many respects the two halves were going their own ways.
All these measures of division, like the increasing autocracy which they accompanied, were directed towards a more efficient assertion of power against internal rivals and foreign enemies. Imperial propaganda does not refer to the former peril except in general, delicate, allusions to the Security of the Emperor. But there is continual stress on his role of conquering defender against the foreign foes who pressed remorselessly on every side. It was pre-eminently as conqueror of the barbarians that the publicity of the time liked to depict its ruler: and the inscriptions on the coinage pointed urgently to his military prestige. This emphasis becomes increasingly notable during the dangers which encompassed the empire under Marcus Aurelius. Forgetting the themes of domestic policy and religious myth which had figured largely on earlier issues, his coins proclaim him as supreme war-lord and warrior. From now on there is incessant concentration on this first and most imperative demand that the Roman people had to make – victorious leadership and prowess.
A statue of Hadrian had shown him with a recumbent captive beneath his feet,8 and Septimius re-enacted in person the time-honoured practice of trampling down a fallen enemy with his horse.9 The theme developed to a feverish pitch under Constantine and his successors, who reiterate their victoriousness as perpetual conquerors of all races everywhere. And while the enemies who were crushed, in propaganda if not in fact, often included the Persians, these retaliated in the same vein, showing a probably fictitious scene of Shapur I trampling the Roman Gordian III (p. 25).10
The dangers and disasters of the mid-third century made people long to revere the saviour-qualities, if any, in the emperor. Gallic professors praising Maximian, Constantius I Chlorus and Constantine at Augusta Trevirorum repeat continually that these rulers have saved the world from catastrophe. Never has devotion been expressed in language so unrestrained; never has there been such intense hatred and fear of the barbarian foes. The man who could ward them off was surely the elect and companion of gods, and when Constantine made Christianity the state religion he, too, was seen to be in a special relation with his deity (pp. 171, 180).
This same aggrandisement of the emperor was reflected in imperial ceremonial, which developed into a formidable pattern not far removed in spirit from the customs which prevailed at the contemporary court of the Persian enemy.
A greeting ceremony for Caracalla had already shown the development of hierarchic etiquette,11 and obeisance or kow-towing, of some more definite and subservient nature than hitherto, is taken for granted by third century writers.12 The greeting (salutatio)received by earlier emperors was superseded by the prostration (adoratio) previously reserved for gods or kings. Elagabalus had already attempted to introduce prostration, but it remained for Diocletian to make adoratio a formal institution of the court. The move was part of a growing tendency, going back to various Greco-Roman and oriental traditions, to submerge respect for the emperor’s personal qualities in a general reverence for the imperial office in the abstract. The obeisance to Diocletian worshipped the purple rather than himself. Such practices took permanent root; many features of his court and its behaviour and titles, formalising earlier usages, led on to a thousand years of Constantinople, and to the ceremonials of Teutonic kingdoms.
Diocletian and his fellow-Augustus and their two Caesars were withdrawn from human contact, living in an awe-inspiring seclusion which was inaccessible to the security hazards of soldiery and disaffected subjects. The infrequent public appearances of the rulers, staged in imperial buildings designed for these occasions (p. 106), were spectacular epiphanies in gorgeous robes. Already for a century the dress of the emperors had been gaining in magnificence. From the time of Marcus Aurelius onwards the coins, and particularly the commemorative medallions which exploited less conservative aesthetic possibilities, increasingly concentrated on this aspect of autocratic grandeur. Gold embroidery as a permanent feature of the imperial mantle and tunic seems to date from Commodus,13 and then, as the prejudice against emperors wearing military costume in Rome began to weaken, medallion portraits depict many a splendid variety of richly decorative shields, eagle sceptres, Olympian fringed cloaks (aegis) worn off-shoulder, and half-length representations of the imperial figure in godlike semi-nudity–just as, conversely, gods are now sometimes portrayed in the robes of emperors. A painting displays Septimius clad in a glorified variation of the costume worn at generals’ Triumphs, and Severus Alexander’s medallions show him decked out in a new elaboration of this triumphal guise.
During a brief interlude in the Severan dynasty (217–18), the emperor Macrinus appeared in public wearing brooches and a breastplate lavishly adorned with gold and precious gems, extravagances of which the Roman soldiery was said not to approve because they seemed more appropriate to barbarians and women.14 The consular robes, too, were transformed into bejewelled splendour on coins of Gallus (251–3).15 This sort of gala costume, richly embroidered with elaborate stitching, becomes ever more dazzling and stylised in a series of coin-portraits of Probus. Emperors now exhibit chain-mail of gaudy magnificence, and the laurel and oak wreaths traditional to Roman leaders are beginning to be replaced by diadems, which had always been understood to represent autocracy. A silver medallion of Gallienus seems to show such a diadem; Aurelian was said to have worn one, and a medallion of Numerian (283–4) displays a diadem with a star above the brow. Diocletian and his fellow-tetrarchs wear helmets studded with precious stones, and their grim features contrast strangely with the gold-hemmed gorgeousness of their robes. Then the heads of Licinius and Constantine are framed in a nimbus or halo which betokens the unearthly light streaming from their countenances, the outward expression of their inward divine illumination (p. 172). During the fourth century there is little to choose in hierarchic splendour between the Romans and their Sassanian enemies or ‘brothers’, except that the Romans did not imitate the pleated ribbons, necklaces and ear-rings of the Persians, or their numismatic portrayal of monarchs each with his own distinctive crown. On the Roman side, no one was more fond of ostentation than Constantine, whose regal profusion of locks is adorned by diadems studded with pearls. Such glorious displays are the outer sign of the new Christian absolutism defined and described by Eusebius of Caesarea in Palestine (260–340) in his enthusiastic biography of Constantine. This pioneer ecclesiastical historian adapted the traditional Greek philosophies of kingship to Constantinian use, praising contemporary autocracy as the archetypal form of government which corresponded to God’s monarchy and opposed the anarchic disorder of democratic equality.16
The emperor, encrusted with jewellery, had lost all personal characteristics except those expressible in the superlatives of veneration, and the statues which attempt to convey this grandeur had frozen into a supernatural immobility far removed from classical humanism (p. 96). Indeed during their public appearances the rulers themselves were as rigid and immobile as their statues. On the single occasion when Constantine’s son Constantius II visited Rome (357), he moved through the city turning his eyes neither to the right nor the left. When the wheels of his carriage shook him, he did not even nod his head; and he never moved his hands. He seemed to onlookers like an effigy or simulacrum of a man.