Emperor leo iii the isau.., p.4
Emperor Leo III the Isaurian, page 4
Inscription commemorating the successful defence of Nicaea and the restoration of its walls.
Chapter 1
From Heraclian Stability to Military Anarchy – The Roman Empire of 685
‘Victory at all costs, victory in spite of all terror, victory however long and hard the road may be; for without victory, there is no survival.’
Sir Winston Churchill
Unexpected Survival
It is something of a surprise that the Roman Empire survived the seventh century. The Persians and Avars had come close to extinguishing it in the 620s, while the armies of emergent Islam had altered the Roman landscape forever through the 630s and 640s. However, the decisive and perhaps expected hammer blow had not come on either occasion. The Avaro-Persian siege of Constantinople in 626 made little impression, while internal strife prevented the Arabs from launching an all-out assault on the Roman capital – the so-called ‘First’ Arab Siege of Constantinople of the 670s seems much less a full-blown siege and more a half-hearted blockade and raiding of Constantinopolitan waters.1 That said, while the weakness of imperial opponents in the face of the Land Walls of Constantinople had saved the Roman Empire, the Mediterranean world of 685 looked significantly different than it had in 600. Egypt, Libya, Palestine, Syria, Mesopotamia, Armenia and virtually the entire Balkans had been lost to the Romans, with Anatolia facing annual raids. Many of these losses would be permanent.
It was not just through the strength of the Constantinopolitan defences that the Roman state persevered through decades of haemorrhaging territory and resources. When faced with such an existential threat, even though militarily exhausted, the Roman people and imperial infrastructures proved resilient. They were aided by the fortune of coming under the leadership of a dynasty of skilled military and political commanders – the Heraclians. The founder of the dynasty, Heraclius won the war against the Persians by leading an invasion himself and led a somewhat orderly retreat from the Levant to defensible positions in Anatolia in the face of the Arab advance. Constans II used the somewhat solid base provided by his grandfather to achieve limited success, winning a favourable treaty from the Umayyads, defeating some Slavs in the Balkans and making some initial strides against the Lombards in Italy. Constantine IV stood up to two usurpers and led the resistance to whatever actually constituted the ‘First’ Arab Siege of Constantinople, while Justinian II won victories over the Arabs, Slavs and Ravennate rebels.
The successes of the Heraclians in steadying the ship, on top of the preeminent position it had enjoyed before the troubles of the seventh century, meant that despite the substantial losses of territory, the Roman Empire of 685 still encompassed enough land to continue to defend itself and go on the offensive on various frontiers. That Roman resilience, inherent and inspired by the Heraclians, would be needed, as through the early life of our subject, Leo III, the empire would continue to lose territory, facing the definitive loss of Africa, further erosion of its position in Italy and more grinding warfare against the Umayyads in eastern Anatolia and the Caucasus.
The continued external pressures on the Roman state and the internal ructions it caused meant that overseeing the survival of the empire on their watch did not immunise the Heraclians from violent scrutiny: Heraclius faced a coup from within his own family; Heraklonas was deposed in a bout of familial infighting; Constans II was assassinated by his chamberlain; Constantine IV faced a plot centred on his brothers; and Justinian II was deposed not once but twice. And this does not take into account the other members of the Heraclian family and others done away with by various emperors for the sake of the succession and/or perceived internal security. It was this increasing ‘Military Anarchy’ that brought down the Heraclian dynasty and was to provide the setting for Leo III’s accession to the imperial throne.
Inside the Walls
One of, if not the, most significant factors in the survival of the Roman Empire in the seventh century was the position and defences of the imperial capital, Constantinople. Being founded only in 330, on the surface, this ‘city of Constantine’ was a veritable urban youngster when compared to various cities still within the empire at the time – Thessalonica was founded in 315 bc, Rome traditionally in 753 bc, while Athens had been continuously occupied since 3000 bc.2 However, the ‘founding’ of Constantinople in 330 was in fact a second (or even third) urban re-founding on the site.
The settlement that would eventually become modern Istanbul was traditionally founded in 667 bc, reputedly by the Megarian king Byzas, although it may be that that name was instead of Thracian origin.3 This seeming eponym gave the city the name Βυζάντιον/Byzantion. That said, there were at least two other settlements recorded in what is now Istanbul that may predate the foundation of Byzantion. Pliny the Elder records that Byzantium was ‘formerly called Lygos’, which seems to have been focused on the Sarayburnu/Seraglio Point, while the second-century geographer Dionysius of Byzantium lists another settlement at the head of the Golden Horn called Semystra, after a nymph of the same name, which almost became the site of the Greek colonisation but for poor omens.4 It would seem that both of these pre-‘Byzantine’ settlements were founded by local Thracians. Furthermore, recent archaeological finds in European Istanbul would seem to predate not only these historical settlements but also the millennia-old Copper Age occupations – 5500–3500 bc – on the Asian side of the Bosphorus by up to 1,200 years.
The potential for Byzantion having been ‘refounded’ already before it became the ‘city of Constantine’ comes in the second century ad. During the civil war that erupted upon the assassinations of Commodus and Pertinax in 193, Byzantium sided with one of the opponents of the eventual winner, Septimius Severus, and faced siege and sack at his hands. The damage was so extensive that when Severus undertook the rebuilding of the city, it was given a Romanised plan and briefly renamed Augusta Antonina after his son, Caracalla (Marcus Aurelius Antoninus).
It was the site’s natural defences, being surrounded on three sides by the sea, and position astride the divide between Europe and Asia that so attracted Constantine in the early-fourth century. He was far from the first Roman to recognise this, shown by Cassius Dio’s strong criticism of Severus’ razing of Byzantion, which he called ‘a strong Roman outpost and a base of operations against the barbarians from Pontus and Asia’5 (and of course, Severus showed that he recognised its strategic position by rebuilding the city). As he intended for Constantinople to be his imperial capital, Constantine initiated a building programme to bedeck the city with incredible architecture – the forums of Constantine and the Ox, the Great Palace, the Hippodrome, the Augustaion, the Church of the Holy Apostles, later to be added to by Hagia Sophia and Hagia Eirene to name but a scant few.
But it was not just sublime imperial and holy architecture that was to adorn the ‘city of Constantine’. While the geographic location of the city offered east-west trading routes, natural harbours and a strong defensive position, it was not without its drawbacks. Chief amongst them was the site’s water supply or lack thereof. It only had a few small springs and the Lycus, which is sometimes called a ‘river’, was really just a stream. This led the fourth-century rhetorician Themistius to comment that even though the Constantinian dynasty had gone to great lengths to beautify Constantinople, it was ‘girdled by gold but dying of thirst.’6 So for it to become the immense imperial capital Constantine envisaged, Constantinople would need nearly 500 km of channels and aqueducts to bring water from the Belgard Forest in Thrace.7 And once that water entered the city limits, it had to be sent to various vast open-air reservoirs and dozens of subterranean cisterns for distribution to the population.
Another of the drawbacks was its sheer size – as it grew, Constantinople quickly outstripped the capabilities of its hinterland to provide for it. It was fortunate then that Constantinople had an empire to feed it. Its coastline allowed for numerous harbours to facilitate the importation of those resources, with none more important than the grain fleet that came from Egypt. Constantinople not only consumed the products of empire, its harbours and numerous warehouses made it a major trading hub, playing a significant role in redistributing the wares of the world. This immense logistical enterprise enabled Constantinople to grow from a sparsely populated but impressively endowed settlement in the mid-fourth century to overtaking Rome as the largest city in the Mediterranean within a century, possibly reaching over 600,000 inhabitants, if not more.8
A third drawback stems more from the success the Romans made of Constantinople rather than the site of the city itself. Indeed, it is more of a general issue for large concentrations of people in the ancient world. It could well be that refugees from the territorial losses and raids suffered by the Roman Empire during the seventh century actually saw the population of Constantinople increase at a time when the breadbasket of the capital – Egypt – had been permanently lost. Even in normal times, a large, compacted and undernourished population is dangerous; however, since 541, the late-antique world had been wracked by an immense plague cycle. It being a trading hub and centre of naval, military and political power opened Constantinople up to infection from various corners of the empire and beyond. There would be at least two major outbreaks during the Isaurian dynasty, one during Leo III’s lifetime, but it must be remembered that such focus on major outbreaks hides the fact that plague was likely a constant companion for the inhabitants of not just Constantinople or the Roman Empire as a whole, but to the entire Mediterranean world, including Rome’s tribal, barbarian and Muslim opponents.
Its central position between Europe and Asia enabled Constantinople to become, not just a trading hub, but a nerve centre of imperial rule the like of which the Roman world had perhaps not seen since before the crisis of the third century. Constantinople could be seen as almost an island city-state supported by and administering its provinces, power emanating from the imperial seat, which the emperor rarely left for any length of time. This concentration of power in Constantinople increased the resilience of the Roman state as a whole, for as much damage that could be done to the provinces, the capital could still emanate that power and represent a focus of imperial continuity. Gradually, it could be said that Constantinople became not just the empire’s capital, but the empire itself.
However, such a concentration of imperial, administrative, cultural and religious power and influence made Constantinople itself a very appealing target for an invader. Being the main bastion of the Roman Empire meant that Constantinople needed to be well-defended. And it was. The rapid expansion in population meant that even by the end of the fourth century, the defences built by the Constantinians were already too small for the city. Their replacements have become known as the Theodosian Walls, as they were usually considered to have been begun during the reign of Theodosius II under the direction of the praetorian prefect Anthemius; however, there is some evidence that the walls were begun in around 405/406 and were therefore planned and begun under Theodosius’ father, Arcadius.9
Once completed, the scale and scope of the Theodosian Walls were truly epic. They encompassed an area that doubled the size of Constantinople, which was already not a small settlement. And in terms of defence, these were not just ordinary run-of-the-mill fortifications – the Theodosian Walls were the greatest fortifications of the ancient and medieval world. Approaching from the west, an enemy attack faced a 20m wide, 10m deep moat and then a 20m killing zone just to reach the outer wall. That first circumvallation was 8.5m high and 2m thick, with 96 towers placed at 55m intervals.10 If the attacker got to and over this first line, he was then faced with another 20m terraced killing zone before reaching the main inner wall, which was 12m high, 5m thick and also crowned by 96 towers.
While not as comprehensive as the Theodosian land walls, Constantinople also boasted significant upgrades to the original seaward defences of Byzantion. It was initially thought that these upgrades came at the same time as Constantine’s refounding of the city, but there is no surviving reference to them before 439, when Cyrus of Panopolis, the urban prefect of Constantinople, was ordered to repair the city walls and complete them down to the sea. But even this appears to be an error repeated by various later sources such as Theophanes and the Chronicon Paschale. Some significant repairs to the land walls were carried out by the praetorian prefect, Constantine, after an earthquake in 447 and he is accredited by Patria I.73 as connecting the sea walls to the Theodosian land walls. Indeed, the very existence of any substantial seaward defences in the same order of magnitude as the land walls before the seventh century has been doubted. The lack of mention of seaward defences during the siege of 626 has been noted, although the supremacy of the Roman navy in the face of the Avars and Persians might negate the need of such mention. There are also very limited fifth-century finds of associated sea wall brick work. There is perhaps no extant contemporary mention of the sea walls until the turn of the eighth century.11
Whenever they were completed, the sea walls were similar to the land walls in terms of appearance but were much less intricate. They were made of a single wall, which was not as tall as the land walls. Only in the various harbours dotted around the coast was there a second circuit. Part of the reason for the sea walls not needing to be as formidable as the landward defences were the strong currents around the city, which made it extremely difficult to make an orderly attack, particularly on the southern and eastern sides, while the northern approaches were defended by the Golden Horn, an inlet that provided a magnificent natural harbour, the entrance to which was itself guarded by sizeable towers both from within Constantinople itself and the satellite city of Galata on its northern side. On top of that was the strength of the Roman navy and its own ‘secret weapon’ in the form of ‘Greek fire’. Furthermore, the seaward defences would see major refurbishment and an important upgrade in the early-eighth century; an upgrade that was to have a significant impact on the reign of Leo III.
This combination of vast land and sea fortifications posed a conundrum for any and all attackers. Between their construction and the breaching of the sea walls in 1204 by the Fourth Crusade, the only successful attempts to capture the city were undertaken by Romans during times of civil war, and none of those overcame the defences through force – they relied on betrayal from those within or sneaking into the city due to local knowledge. Indeed, the land walls would only be rendered vulnerable by the invention of the cannon a millennium after their construction. And even then, large sections of the Theodosian Walls still stand today.
Outside the Walls – Themes
The defences of Constantinople might have provided the Roman Empire with a bastion of incredible strength, durability and resilience, but that does not mean that the empire itself had not changed significantly. A quick glance at a map will show that, but not all of these changes were enforced by the cataclysmic events of the seventh century. The most obvious cartographic revelations would be the loss, reclamation and then gradual loss again of the western provinces of the empire since the fifth century. However, digging down a layer further than purely territorial, there had also been some important administrative developments in reaction to pressures faced by the empire in the sixth century.
The first of these major changes came in the west. Distracted by the Avars in the Balkans and the Persians in the east, the emperor Mauricius (582–602) felt that the administrative and military problems faced by Roman Italy required the creation of a new provincial organisation: the exarchate. This saw Italy divided into a series of duchies and placed under the regional command of the exarch of Ravenna, who held civilian and military authority. A similar administrative arrangement followed in Roman North Africa and the islands of the western Mediterranean (apart from Sicily), which were aggregated under the command of the exarch of Africa from Carthage.
The idea was for the exarch to be able to administer the western regions without having to look to Constantinople for leadership. However, there were issues with this. Such a dissemination of authority relied on the exarch being able to impose his imperially-invested power – in Italy, the interjection of the Lombards made that difficult. And as the authority and territory of the exarchate shrank, the various provincial duces began to act independently. Furthermore, the concentration of civil and military power in the role of the exarch coupled with the geographic separation from the emperor meant that the exarch would not always act in accordance with imperial wishes – Ravennate exarchs are seen siding with the papacy against the emperor and with the Ravennate archbishop against the papacy and the emperor, while the African exarchate hosted two separate usurpations against Constantinople. And this is just a small snapshot of the exarchs who died in post either fighting for or against the empire.12
The African exarchate was much less troubled than that of Italy. While Carthage did have to deal with the occasional raids of the Berbers and internal issues regarding pay, the Ravennate exarch had similar financial troubles, but also the Lombard kings and dukes, intransigent bishops and increasingly independent underlings gnawing away at his power and territory. And yet, by the turn of the eighth century, it was the African exarchate that had disappeared, swept away by Arab invasion. That is not to say that the Ravennate exarchate was in much better shape. The exarch was in the process of being relegated in importance in Italy.
While these exarchates offered well over a century of imperial service, it is difficult to determine if they really provided any substantial benefit to the empire, beyond allowing the central government to effectively ignore its western outliers as wasteful burdens rather than useful assets. That the emperors would continue to accept an abrogation of direct control over imperial territory is very telling. However, even if the exarchates and their dissemination of power were of little real use and/or a blemish on the sovereignty of the emperor, the social, political, religious and military problems that had initiated their creation had not abated; they had only become worse and worse. The collapse of the Danube frontier and the loss of the eastern provinces forced the Heraclians to follow a similar exarchate policy at the core of the empire. This would become known as the ‘theme system’.
