Sunday, February 21, 2016

Prelude to the Barbarian Conspiracy of AD367

by James Collins

The Great Conspiracy of AD367 is without doubt one of the most tantalising and enigmatic events in Romano-British history.

Contemporary records, primarily from the Roman historian Ammianus Marcellinus, indicate that the Roman garrison on Hadrian’s Wall rebelled and allowed northern tribes (Picti, Scoti, and Attacotti) to penetrate the frontier and lay waste to the northern provinces of Britain.

At the same time, and purportedly in union, Saxon and Frankish war-bands invaded the British and Gaulish coasts. The assailants ransacked the towns and brutalised the inhabitants, thrashing a trail of devastation through the island which can be corroborated by archaeological records of the time.

This enticing scenario was one of the reasons I chose to set my novel, Sol Limitis, in the prelude to the incursions of 367. As the first part of a trilogy, I wanted to explore the effects of the Great Conspiracy from a ground-level perspective, experiencing this terrifying and violent period of British history through the eyes of my characters caught in the middle of it.

But the concerted attacks of 367 were not an aberration; on the contrary they were the natural culmination of a series of dark and bitter years stretching back to earlier in the C4th. Peter Salway, the noted historian of Roman Britain, wrote in his seminal work that, “one cannot help suspecting that AD340 marks the true beginning of Britain's troubles.”

C16th edition of Ammianus
Marcellinus’ Roman History
A large portion of my research for the novel involved getting to grips with the tenor of Romano-British life in the mid-C4th century.

And this, by most accounts, was grim indeed.


A few years after the death of Constantine the Great in 337, his brother Constans (one of three siblings to assume the role of Augustus) made a personal trip to Britannia. During his visit he reinforced the military presence and attempted to bolster their defences by creating the role of the comes litoris Saxonici, (‘Commander of the Saxon Shore’, referring to the string of forts guarding the vulnerable coastline along the east and south of Britain) and forming the areani, roving agents tasked with working beyond the frontiers.

The situation in Britain must have been dire indeed to warrant such drastic personal intervention by Constans; even the subsequent incursions of 367 did not see the emperor himself set foot upon British shores.

It’s presumed that at this time Britain’s military was woefully depleted following its likely absorption into Constantius II’s army for his failed invasion of Italy in 340. Archaeological evidence suggests there was widespread destruction of northern forts and towns dating from this period, and presumably the diocese was suffering intense pressure from the northern tribes. It may be that Constans created the areani to monitor the terms of his peace-treaties with these groups.

Remains of the Saxon Shore Fort at Portchester.
The D shaped towers are Roman,
adopted into a later medieval castle structure.
We have no detailed records of British events in the following 17 years, though it is likely that there were ongoing small-scale battles along the frontiers. We next hear of Britain in 360 when Emperor Julian received reports of Picti and Scoti breaching their concord and ransacking frontier towns. The magister militum Lupicinus was sent to Britain along with four units of the field army in order to quash these insurgences. Julian’s intention here may have been to strengthen the strained frontiers and instigate a campaign of resistance, but due to imperial politics Lupicinus was recalled and any long-term defence strategy was curtailed.


In addition to the incessant threat of invasion from all angles, the Romano-British also suffered from the fluctuations of their incumbent emperors’ religious devotions.

Although Constantine the Great introduced tolerance for Christianity alongside Paganism, subsequent Christian emperors tended to be more hard-line, effectively driving pagan practitioners underground. When Magnentius defeated Constans in 350 and became de facto emperor of the west, he offered a respite to pagans, legitimising their practices and drawing them into the open. However, he was shortly succeeded by Constantius II, a fervid Christian who reinstated the death penalty for these recently legitimised pagan practices.

Britain was ripped asunder along a key pagan/Christian division which saw the pagans bearing the brunt of Christianity’s intolerance for competing religions.


Magnentius was a usurper raised to the purple by an army dissatisfied with the Emperor Constans. After Magnentius’ defeat by Constantius II at the Battle of Mons Seleucus in 353, Constantius sent a notarius to Britain to identify and eliminate those factions which had supported the usurper and attained power under his brief rule.

This infamous notarius was Paulus, nicknamed Catena (‘The Chain’) due to the ferocity and savagery with which he persecuted the Britons during this period.

Paulus instigated a series of protracted persecutions to such a degree that, as Salway explains, “suspicion became endemic, and no one against whom an allegation was made escaped.” Such limitless persecution can be seen to pre-empt the C17th century witch-hunts of Matthew Hopkins, or even the political purges of the C20th: bureaucrats given carte-blanche for indulging their sadistic whims and empowering the discharging of personal grudges amongst the populace. Certainly Paulus Catena seemed to relish the opportunity for spreading terror throughout the island: it is likely that the notarius overstepped his imperial mandate in the breadth and severity of his purges, though his actions were subsequently endorsed by Constantius.

The injustice the Britons suffered under Paulus was so dire that the vicarius of Britain, Flavius Martinus (a man notably loyal to the emperor) was moved to petition for leniency under threat of his own resignation. He was duly ignored by Paulus who reciprocated by making false accusations against Martinus and his staff. Incensed and desperate, Martinus tried to attack Paulus with his own sword, but was defeated and took the only option available to him: suicide.


Alongside political and religious purges, and endless conflict from tribes pressing at her frontiers, Britain also suffered from wide-scale military corruption and general societal dissolution.

AHM Jones in his book The Later Roman Empire explores how officers would frequently neglect their troops on the frontiers, especially from the middle of the C4th onwards: “Some officers exploited their men shamelessly,” he writes, explaining that many lacked arms, uniforms and even boots. Paraphrasing a C4th Libanius speech, he asserts that the soldiers were “hungry, cold and penniless owing to the peculations of the duces and tribunes, who intercepted what the government provided for them.”

Map of C4th Infrastructure for
overview of the layout of Roman Britain
It was not only the higher ranks who were corrupt. We know from the historian Ammianus that the areani had been abandoning their positions for some time and had been betraying their Roman masters for money: “[they had] fallen into bad practices…[and] had been undeniably convicted of yielding to the temptation of the great rewards which were given and promised to them, so as to have continually betrayed to the barbarians what was done among us.”


Valentinian was the incumbent emperor when he received news of tribal forces acting in concert to attack Britain which had been, according to Ammianus, “reduced by the ravages of the united barbarians to the lowest extremity of distress.” In the course of which at least two of the most senior military commanders (including the comes litoris Saxonici) were either killed or taken hostage. The united tribes were ransacking forts and towns, and looting, pillaging and raping their way through the country. This threat was compounded by the rise of Roman deserters swapping sides, or turning to banditry to further prey on an already devastated population.

This concept of a united barbarian army was a terrifying prospect for Rome whose military superiority depended largely on the lack of a cohesive and unified enemy. Such cooperation implied the presence of powerful charismatic leaders tying together these disparate tribes to threaten their common enemy. This latter part of the C4th was to see the emergence of such leaders amongst the barbarian peoples, ones who could talk to emperors as peers and, if they chose, rise to high ranks within the Roman politico-military hierarchy.

To counter the situation in Britain, Valentinian sent one of his top generals, Theodosius, at the head of an army. Eventually, using counter-attacks, ambuscades and overwhelming force, Britain was back under Roman control and the invaders repulsed; at least temporarily. Theodosius rebuilt forts and cities, strengthened the garrisons, and dissolved the treacherous areani.

A mere four decades later, Britain would cease to be under Roman control for good.

All the available evidence points to a bleak and desperate period of history in the decades leading to the Great Conspiracy of 367. I chose to set my novel Sol Limitis in the winter leading up to the main penetration of Hadrian’s Wall by the northern tribes, and this was because I wanted to focus on the landscape and the inhabitants of this period: scared and beaten people living in squalid, depressed conditions, wearied by endless attacks, religious and political purges and inherently suspicious of each other and, crucially, of Rome. I wanted to show the limitanei, those frontier soldiers grafting at the limit of the empire, as poverty-stricken and ill-equipped mercenaries, hardened warriors as indifferent to the concept of romanitas as they were to a notion of authority that extended beyond their own garrison commander. This was the backdrop into which I wanted to insert my protagonists, and retrieve a ground-level perspective of the events leading up to the incursions.

As a fiction writer, I feel challenged to embrace those aspects of history which others may find unpalatable, and not be afraid of tackling the darker and bleaker aspects of a given period. I believe all authors of historical fiction have a certain degree of responsibility to investigate and invigorate the tribulations of the long-forgotten peoples and to do so in a manner that neither glorifies nor sanitises their hardships according to the tastes of modern readers.

Ruins of the Roman fort of Aesica on Hadrian’s Wall

Roman Britain, Peter Salway, Oxford University Press, 1992
The Roman History of Ammianus Marcellinus tr. C D Yonge, G Bell & Sons, 1911
A.H.M. Jones, The Later Roman Empire, 1964

Media attribution:
[Fig 1] Photo: Feldkurat Katz (
[Fig 2] Photo: Geni Licensed under GFDL CC-BY-SA (
[Fig 3] Based on Jones & Mattingly’s Atlas of Roman Britain licensed under Creative Commons Attribution-Share Alike 3.0 Unported (
[Fig 4] – author.


James Collins is an author, editor, freelance journalist and recovering archaeologist. Born in Stoke on Trent in 1979, he studied archaeology at the University of Nottingham and went on to work as an archaeologist in the UK and abroad. Tired of wallowing in muddy holes for a living, he survived various unsavoury menial jobs before catching his breath in the construction and renewables industries for more years than was healthy. He is currently working towards being self-employed and to be able to get paid for doing what he loves: writing. James also plays and teaches classical guitar and spends most of his spare time studying the Daoist arts.

Twitter: @JamesDomCollins


  1. Thanks Annie - I found it to be a fascinating period of history! - James

  2. Thoroughly enjoyable post - thank you!

    1. Glad you enjoyed it, Alison - thanks for reading!

  3. Interesting article, Sol Limitis is excellent too.

  4. Excellent article and novel too.

  5. Enjoyed Sol Limitis, James. When will the second volume be published?


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