How did the Roman state meet these necessary conditions for maintaining the empire from Constantine to Justinian? The later Roman Empire relied on an elaborate ideology of rulership, which was projected in the grand style by official works of art and literature, and also at a routine level by many aspects of political communication.
A notable example drawn from political life in late antiquity, which was designed precisely to emphasize both the hierarchy of power and the ideological unity of the Roman Empire, was the use of acclamations on public occasions. These repeated, rhythmical chants were an ubiquitous phenomenon in public life. Our sources preserve detailed records of several such occasions. One was the forty-three acclamations which hailed the publication of the Theodosian Code in the Senate at Rome on December 25, 438.6Seventy-five acclamations greeted the appearance of a new provincial governor in Osrhoene, delivered on behalf of the city of Edessa in April 449.7 Twenty acclamations, perhaps of the early sixth century, which were subsequently inscribed on columns at Aphrodisias in Caria, were delivered in honor of a prominent local citizen and benefactor, Albinus.8 A remarkable acclamatory dialogue was staged in the hippodrome of Constantinople during the events of the Nika riot between members of the Green and Blue factions and a speaker for the emperor Justinian.9 Acclamations took a distinctive ritualized form, although their wording was naturally appropriate for the particular occasion that they celebrated. They began with an invocation to God, and followed this immediately with good wishes for the emperor's health and long life, for his continued rule and for his victories. These then normally led to acclamations on behalf of the Senate, of the great state officeholders, and of imperial officials. A law of 380 explicitly indicated that a group of senior civilian officials, namely the quaestores sacri palatii, the magistri officiorum, and the comites utriusque aerarii, were entitled to be hailed by acclamations, as were the praetorian prefects (CTh. 6.9.2). Acclamations on major state occasions might be delivered either in the presence of the emperor, or, much more frequently, in his absence. They were delivered by groups gathered for such occasions, and thus symbolically expressed the wishes of the whole people. These rituals, repeated across the empire on countless occasions, echoed not only the ideology but the power structure of the Roman Empire, and were designed to validate the role of the emperors at the summit of the imperial hierarchy of authority.10
The standardized formulae of acclamations had their written counterparts in all official documentation of the state's activities. The imperial titles at the beginning of public inscriptions and other documents embodied the message that the powers of the emperor were eternal and unchallengeable. At the same time they differentiated between individual rulers. The images and wording used on imperial coinage were conceived in the same way. They identified the particular ruler responsible for issuing the coinage by using a coded pattern of symbols that linked him to his predecessors. A coin could thus be identified in the first instance as an imperial issue, and then as that of a particular emperor. The charisma of the divinely appointed rulers was thus routinized, but their authority was not diminished. Panegyric oratory promoted the idea of imperial rulership in a more sophisticated way, but conformed to similar principles. While individual speeches were tailored to the achievements and policies of particular rulers, they drew on a repertoire of themes that characterized the role of all just and righteous rulers. One of the most significant developments of this imperial ideology was the gradual integration of Christian ideas within a tradition that had its origins in classical ideas about kingship. However, apart from the late works of Eusebius, his Tricennial Oration and the Life of Constantine, which develop an original and new ideology of Christian rulership,11 it is striking that overt Christian symbolism is remarkably absent both from the panegyrics written for fourth-century rulers, and from the monuments set up for them.
Christian symbolism also played only a limited role in the public art of the fourth century. This point is demonstrated by two of the most elaborate imperial monuments of the period; the arch of Constantine in Rome, and the sculpted reliefs on the base of the obelisk set up by Theodosius I in the hippodrome at Constantinople.
Constantine's arch, set up next to the Colosseum by the Roman Senate and people, honored the emperor at his decennalia in 315, on the occasion of the tenth anniversary of his becoming Augustus (Plate 5.1). It is instructive to distinguish the general from the specific message conveyed by its famous decorative reliefs. Recent research has shown that the arch was not originally designed for Constantine. Foundations appear to have been laid in the early empire for a structure that was never built. The realization of the plan was taken in hand by Maxentius, during the five-year period from 307–12, when he claimed the title of Augustus and was effective ruler of Italy and Africa. Two-thirds of the building, as far as the lofty attica, wholly constructed from spolia, and including the famous series of re-used imperial relief tondos and panels, had been completed before Maxentius' death in 312. The Constantinian portion consists of the attic story, which was made from brick and merely faced with marble cladding. This includes the prominent dedicatory inscription, and the statues of barbarians, placed at the top of the pilasters of the façade. In addition, a one-meter-high frieze was slung like a girdle round the piers of the arch, and depicted the victories of Constantine in the campaign against Maxentius, his adventus into the city of Rome, and his address and liberalities to the people (Plate 5.2). Above the frieze at the west and east ends, two tondos were added by the Constantinian sculptors, one showing the Sun god, the other the Moon goddess. The design of the frieze was essentially conventional. It combined the themes of the emperor's triumph over a usurper, his civility towards Rome's dignitaries, and his generosity towards the Roman plebs, and portrayed them in the visual equivalent of a panegyric speech. The Constantinian carving is often crude and schematic, but this is in part due to the fact that the sculptors had to work on scaffolding in situ, rather than prepare their work in a workshop beforehand. The aesthetic and visual impact of the Constantinian frieze is overshadowed by the program designed for Maxentius. This involved the selection and re-use of eight great circular tondos from a monument built for Hadrian, all showing the emperor in scenes of hunting or sacrifice, another set of Antonine friezes, perhaps for Marcus Aurelius, displaying the emperor engaged in a further sequence of great public occasions, which were placed in the attica, and two enormous frieze blocks, placed on either side of the central passageway, from a monument for Trajan, with scenes of a battle and of the victorious emperor. The redeployment of these earlier sculptures, which must already have been familiar to Roman viewers, deliberately evoked the new emperor's place in the succession of great rulers of the past, but it is of course important to realize that the new emperor for whom they were originally designed was Maxentius. Constantine saw fit to inherit all the essentials of his predecessor's design, before he (or his advisors) devised the new frieze which commemorated the overthrow of the usurper. The only modification to the early imperial sculptures was to re-fashion the imperial heads into the likenesses of Constantine and his father Constantius. We see precisely the same affirmation of the legitimacy of imperial rulership in the comparisons that writers of the fourth century made between the emperors of their day and their illustrious predecessors. The arch and its sculptural program signified the embodiment of Roman power in the person of the emperor and the ritual authority of the principate itself. The achievements of Constantine were subsumed in this larger picture.12
Plate 5.1 The Arch of Constantine at Rome (DAI Rome/photo Sansaimi)
Plate 5.2 The Arch of Constantine. Constantine (the head is missing), seated, surrounded by members of his court, distributes largesse to members of the Roman aristocracy, who are depicted wearing the heavy togas of Roman citizens (DAI Rome)
The Theodosian base in Constantinople presents another strategy. The twenty-meter-high obelisk was erected on the central spina of the hippodrome to commemorate the victory of Theodosius I over another usurper, the tyrannus Magnus Maximus (Plate 5.3). One set of reliefs, on the lower part of the socle, showed scenes of chariot racing, pantomimes, and dancers, as well as a vivid representation of the laborious transport and setting-up of the obelisk itself. The main pictorial program was displayed on the upper part of the base. The four sides of the monument displayed the emperor in a series of key symbolic relationships. On two of them he appears seated in the loggia which overlooked the arena, accompanied by the other family members with whom he shared power; Valentinian II, and his designated successors Arcadius and Honorius. In both these scenes the emperors were variously accompanied by high civilian and military dignitaries and by members of the armed imperial bodyguards. They thus represent the ruling heart of the empire. However, it is equally important that the reliefs also depict packed rows of spectators, the common people of the city, who in this context represented the mass of the emperor's subjects. In reality, after the fourth century, contact between the emperor and the common people was largely restricted to ritualized moments such as this one. The base of the Theodosian obelisk is the first monument to depict the crucial encounter of the east Roman ruler with his people in the hippodrome (Plate 5.4).13 The stone monument thus mirrored in idealized form the actual encounters between the ruler and his subjects which took place in the same location. By including the most important members of the imperial family and leading figures of the state, the monument asserts the legitimacy and authority of the whole dynasty.
Plate 5.3 The obelisk of Theodosius I, erected on its decorated base in the hippodrome at Constantinople. The later church of St Sophia is in the background (© Joe Tree/Alamy)
Plate 5.4 The Theodosian base in the Hippodrome, front side, depicting musicians and dancers below the imperial loggia (© B. O'Kane/Alamy)
These two monuments carry only the barest hints of Christianity. The inscription on the Arch of Constantine contains the famously ambiguous phrase instinctu divinitatis, “by the impulsion of a divinity,” to allude to the divine help which Constantine acknowledged had been behind his victory over Maxentius. The Theodosian base depicts a solitary military standard decorated with the Christian labarum (the chi-rho sign) beside the imperial box on the northeast side. In this respect there is a marked contrast with an equally famous monument from the early part of Justinian's reign, the surviving panel of the carved diptych, now in the Louvre, known as the Barberini ivory (Plate 5.5). This was not a great public monument, but an infinitely precious miniature, akin in style to the exquisite ivory diptychs which were commissioned to commemorate the holders of the consulship in late antiquity.14 The central panel shows the imperious figure of the emperor, on his rearing horse, ramming his lance into the ground, in a gesture of triumphant conquest. He is attended by figures representing a barbarian, Victory, and Mother Earth. The panel to the left of this (and doubtless also its lost counterpart on the right) showed a bare-headed official presenting him with a statue of victory. The narrow frieze along the base shows further barbarian subjects bringing offerings of a basket of grain, a wreath, and an ivory tusk, as well as a lion and a panther. The whole composition is best interpreted as a symbolic representation of the reconquest of Africa. The iconography of these panels developed classical themes of triumphal rulership, but the upper frieze emphatically manifested the religious ideology, which Justinian himself had introduced into all representations of imperial power. In front of a tondo held up by two angels it depicts the bust of Christ, holding his right hand in a gesture of blessing over the emperor.15 This explicit acknowledgment of God's might and guiding authority is characteristic of almost all forms of official communication under Justinian, but it is important to recognize that this is also an innovation of this period.
Plate 5.5 The Barberini ivory (© 2013 Photo Scala, Florence)
There is a further instructive contrast to be made between this image of the emperor, triumphant in battle, and the dedication mosaic of the Church of S. Vitale in Ravenna, dating to 548. This shows the emperor carrying a basket of offerings. To his left is bishop Maximinus, founder of the church, and three bare-headed clergy, to his right are two civilian courtiers and four armed soldiers of the bodyguard, standing behind an oval shield, decorated with the labarum (Plate 5.6). The overall impression is now devotional, not triumphant, and was determined not only by the ecclesiastical context of the mosaic, but also by the change in the political atmosphere during the later part of Justinian's reign.
Plate 5.6 Church of S. Vitale, Ravenna. The mosaic depicts the emperor Justinian, surrounded by clergy, including the bishop of Ravenna, Maximinus, who is identified by the inscription, with three soldiers of the palace guard, their shields displaying the labarum(© The Art Archive/Alamy)
The symbolic system and visual language of power, which is to be found in all late Roman imperial iconography, was also adopted and manipulated with an equal sureness of touch by the rival empire of the Sassanians. A magnificent series of rock monuments from the central areas of the Persian Empire in the third century depicts the rulers in attitudes of triumph over foreign enemies, piety towards their supreme god Ahura-Mazda, and authority over the courtiers and officials that surrounded them. The finest and best-known of these reliefs date to the third century and depict Sapor I, victor over three Roman emperors, and the mightiest ruler of the third century AD, commanding the twin worlds of Persia and Rome, “king of the Arians and the Non-Arians” as his inscriptions describe him.16 However, it is also instructive to compare another set of reliefs from Taq-e Bostan in northwest Persia, which probably dates to the reign of Khusro II, the rival of Heraclius in the early seventh century. The main panel depicts the king, clad in heavy armor, astride his warhorse (Plate 5.7). Above this he is shown again, being crowned by the divinity, the great god Ahura-Mazda, on whose protection the state depended, and accompanied by a female figure, presumably his royal consort, who is shown holding the severed head of one of his enemies. The whole composition, a wall of sculpture five meters high, is recessed in an arched vault. At the front the tondos of the arch carry winged victory figures that mirror the pose of the angels on the Barberini ivory.17 The overall composition of this great rock monument of late Sassanian Iran is strikingly similar to the Justinianic ivory miniature.
Plate 5.7 Taq-e Bostan. The Sassanian king, Khusro II, clad in heavy armor, mounted on his war horse. Khusro II was Rome's nemesis during the first twenty years of the seventh century, bent on a policy of destroying the Roman Empire (S. Mitchell)