The strategy and tactics of siege warfare in the early Byzantine period from Constantine to Heraclius

by Stephen McCotter

This doctoral thesis, successfully examined in October 1995, arose from the concern that while many scholars have recently dealt with the Byzantine army from a socio-economic perspective, research into how the army actually conducted its operations was neglected. Sieges in particular were largely ignored although they constituted over half of the military engagements in the period from Constantine to Heraclius. Investigations covered how the Byzantines and their enemies attacked and defended fortifications, what weapons they used, why they attacked them, how they treated them after capture, and how the cities were defended. It also examines the changes over time in this area of late antique military operations. This diachronic work was concerned not only with the Byzantine forces, but also with their enemies. Literary statements by late antique authors, to the effect that the ‘barbarians’ were useless when it came to attacking walled cities, had been accepted without question but the fact remained that they captured many. This needed to be examined. To facilitate this, the various armies were grouped according to their level of urbanisation, since siege warfare naturally involves attacks on cities. The aim was to see whether urbanised peoples conducted siege warfare in a more advanced fashion than their less settled counterparts.

The conclusion of the thesis suggests that experience of urban living does not improve poliorcetic ability in its own right. The Visigoths roamed inside the empire for 40 years before settling in Aquitaine, but even then they could still not take cities by assault, and they show no sign of having acquired siege weapons. Yet the nomadic Avars were able to assault cities successfully almost from their first contact with the empire. Thus association with urban living was not the sole determinant of poliorcetic capability, at least not for storming operations. If cities were to be assaulted it was the side with the best weaponry which achieved most, and the urban lifestyle of various peoples seems to have little bearing on this. The significant feature appears to have been the use of the bow. The western barbarian peoples did not make much use of archers and consequently struggled to take towns by force, but when they incorporated the former imperial institutions of the regions they inhabited, including their military establishments, their ability to assault cities improved dramatically. The fact that many former imperial units contained archers would appear to be the key factor in this. In terms of simply gaining control of cities by any means possible, an urban background seems to have influenced the ability of the various peoples. Once they started to live in and around cities, the barbarians understood what urban life required in order to function. It is no coincidence that after the Goths had been living in Italy for a while they appreciated the importance of supplies for a city’s survival. Rather than simply sitting around towns trying to prevent provisions reaching those inside, they actually tried to control possible sources of supply. Hence their capture and garrisoning of Portus every time they besieged Belisarius in Rome. The value of treachery and deception was not lost on them either, witnessed particularly by their attempts to bribe gate-keepers. Thus the various barbarians were just as effective as their more settled counterparts when it came to taking cities. They used different tactics, based on a recognition of their own abilities and deficiencies, to conduct sieges. Successful storming operations were admittedly rare, but it must be pointed out that the Byzantine military handbooks themselves suggested that direct assaults were the last resort rather than the preferred way of taking objectives. Therefore, by avoiding assaults, the barbarian forces were achieving success with the minimum number of casualties, which is arguably military ability at its best.

Other aspects touched on the doctoral work included technology transfer, particularly the introduction of the trebuchet. I believe it may have appeared as early as the 580s, being brought west by the Avars and rapidly copied by the Byzantines and then the Persians. Another point was the increasing influence of Christian beliefs in warfare. The siege of 626 is not unique in terms of popular piety as similar incidents of supernatural defenders of cities appear as early as 337 at Nisibis. It is put into context by demonstrating that divine protection did not only take the form of phantom apparitions, but is evident in reports of bishops manning ballistae, monks defending walls, cities falling because they had not fasted piously enough and other similar beliefs.

Finally, a comparison with former Roman siege operations showed that the Byzantines were not as effective as their predecessors. less effort and energy appears to have been expended in the military conduct of sieges than before. Even the nomadic tribes seem to have been more forceful in their poliorcetic operations, while the Persians appear to have been the most successful and competent of all the forces in late antiquity. While the Roman legions had easily been the preeminent military force in their time, the fourth-seventh centuries were times of crisis when the empire was overwhelmed by widespread military problems and the fact that it conducted as many sieges as successfully as it did is testimony to its ability.


Strategie en tactiek van oorlogsvoering via belegering in de vroeg-Byzantijnse tijd: van Constantijn tot Heraklius

Dit promotieonderzoek is gestart om de leemte te vullen die bestond in het onderzoek naar het Byzantijnse leger, namelijk de vraag hoe het leger zijn operaties, in het bijzonder de belegeringstactiek, uitvoerde. Bronnen uit de tijd zelf spraken erover dat de ‘barbaarse’ legers steden niet konden aanvallen, maar feit is dat ze er wel veel hebben hebben bezet. Zowel het Byzantijnse als vijandige legers werden bestudeerd, waarbij een indeling werd gemaakt van de legers in hun mate van verstedelijkt zijn, omdat belegeringen gewoonlijk steden als doelwit hebben. Op zich, concludeert deze studie, bevordert het gewend zijn aan wonen in een stedelijke omgeving de mate van kundigheid in belegeren niet. ‘Barbaarse’ legers gebruikten andere tactieken die zij beheersten en leerden van hun zwakke punten.