The departure of the Roman legions - a traditional view. From Cassell’s History of England, 1909 edition — The departure of the Roman legions - a traditional view. From *Cassell’s History of England*, 1909 edition

Surprisingly, for a rather obscure episode of ancient history, the end of Roman rule in Britain has been in the news quite a bit in recent years. This is largely because of perceived similarities to the current situation in the UK, and the ongoing attempts of the Westminster government to disentangle itself from the European Union. But, leaving aside such comparisons if possible, what do we actually know about how and why Britain left the Roman Empire?

In the first half of the 4th century, life in the Diocese Britanniarum was apparently pretty good – at least for the wealthier inhabitants who left most of the material traces we use to determine these things. Roman Britain was firmly woven into a vast and complex empire stretching all the way to the Tigris and the upper Nile.

Compared with the Gallic provinces, devastated by civil war and invasion during the chaotic 3rd century, Britain was wealthy, stable and secure. But this very prosperity was perhaps deceptive. The growth of massive country villas – most of those that survive today date from this period – with their luxurious bath suites and polychrome mosaics, might suggest that wealth was increasingly pooling in the hands of a small elite class of landowners. The simultaneous decay of infrastructure in many towns and cities could indicate that this wealth was not trickling down to all levels of society.

This situation – rosy for some – seems to have suffered a major setback in the late AD360s. The specifics are hazy. The contemporary historian Ammianus Marcellinus writes of a ‘barbarian conspiracy’ of Picts and Scots, overwhelming the defences and plundering the provinces, combined perhaps with a breakdown in military discipline and major civil unrest. Recent historians have tended to question the whole narrative of ‘barbarian invasions’, which often appears as a convenient deus ex machina to explain why certain otherwise obscure things happened in late antiquity. But whatever the cause, the security of Britain does appear to have suffered, and quite possibly the confidence of the people of the province in the stability of imperial control suffered with it.

Gold solidi from a hoard of 159 coins found near St Albans. They were all minted between AD388 and 408, with the majority featuring Honorius, the presiding emperor at the time that Britain was parted from imperial control. Details from the Portable … — Gold solidi from a hoard of 159 coins found near St Albans. They were all minted between AD388 and 408, with the majority featuring Honorius, the presiding emperor at the time that Britain was parted from imperial control.
*Details from the* *Portable Antiquities Scheme*.

From the 370s onward, there are signs that overall quality of life in Roman Britain was declining steeply. The abandonment and downgrading of both villas and urban areas in this period suggests a reduction in economic and social complexity that to some extent is matched elsewhere in the Roman west, but in Britain appears to have been particularly rapid. While direct evidence for hostile activity is scanty, the number of buried coin hoards from towards the end of the 4th century could be taken as an indication of social unrest. Attacks on coastal areas by Saxon or Pictish raiders, while probably not too extensive, would have contributed to a sense of vulnerability among both wealthy landowners and provincial citizens alike.

Exactly what happened at the dawn of the 5th century to trigger the subsequent upheavals is unclear, but the results would be catastrophic. In AD406, the troops based in Britain – who had possibly not been paid for some time, and may have resented demands for manpower from a hard-pressed imperial government in Italy – threw off the authority of the Emperor Honorius and elevated a soldier named Marcus as their new Augustus. This figure, a historical blank beyond his name, did not last long. Shortly afterwards the Britons overthrew Marcus and elevated in his place one Gratianus, who appears to have been a town councillor of some kind.

Gratianus too was destined for a very brief and ignoble rule. Early in AD407, news reached Britain that, in the dead of winter, a force of Vandals, Alani and other barbarians had breached the frontier on the Rhine and were rampaging across Gaul, heading for the Channel coast. This invasion may not have been as large or as destructive as contemporaries, and generations of subsequent historians, believed. But, after only four months in the purple, Gratianus too was tumbled from precarious power, and his place taken by yet another army officer, who bore the impressively imperial-sounding name Flavius Claudius Constantinus.

*Gold solidus of Constantine III, minted at Lyon. The reverse shows him trouncing a fallen barbarian.*

However, if the people of Britain hoped that their martial new Augustus would secure the shores against invaders, they would soon be disappointed. His eyes on a bigger prize, Constantine III (as he is known today) instead collected up most of the mobile troops remaining in Britain and crossed to the continent, determined both to drive out the barbarians and to extend his rule over the western empire. This, incidentally, is probably the best candidate for ‘the departure of the Roman army’, a scenario much beloved by Victorian and Edwardian artists. But we should not imagine shiploads of Italian legionaries sailing from the British shores: the small British field army, a recent innovation, contained units from Gaul and apparently from Syria, while the frontiers of Britain were largely defended by locally-raised troops and Germanic mercenaries, many of whom probably stayed put. It does appear that the garrisons of several coastal forts, from Portchester and Pevensey to the Kent coast, were moved to the continent around this time, however, as they later turn up in a list of the Gallic field army units of c.AD420.

*‘The Romans Leaving Britain’, by John Everett Millais (1865)*

With their newly-minted emperor and most of his troops off in Gaul defeating the barbarians (in fact he appears to have made treaties with them instead), securing the Rhine frontier, and then battling Honorius’s generals, the citizens of Roman Britain found themselves with little adequate protection against their own worrisome foes. Later chronicles mention Saxon and Irish raids during this period, which would have been almost unopposed with the coasts now thinly defended at best. It was due to the “negligent government” of Constantine III, the historian Zosimus writes, that “the barbarians were emboldened to commit such devastations.”

Not surprisingly for such a fractious people, it did not take long before the Britons had had enough of Constantine III. Zosimus tells the story in passing: “The Britons therefore took up arms… for their own protection, until they had freed their cities from the barbarians who besieged them… In a similar manner, the whole of Armorica, with other provinces of Gaul, delivered themselves by the same means; expelling the Roman magistrates or officers, and erecting a government, such as they pleased, of their own.” [Zosimus, New History, 6.5.3]

So this was not a rebellion against Roman rule in general, but against the rule of an ineffectual usurper, who was at that time caught up in fighting a civil war in Spain and dealing with yet further barbarian incursions on the Rhine. Those doing the rebelling, whether an elite clique of wealthy landowners or some – perhaps more egalitarian – commune of citizens, apparently set up their own government in place of the one they had overthrown, and their rebellion spread across the Channel to Armorica (Brittany) as well. Such grassroots uprisings were not uncommon in the Roman west; the rebels even had a name: bagaudae. But a well known and much-discussed note a little further along in Zosimus’s narrative suggests that there was something more going on here.

“Honorius,” Zosimus writes, “sent a letter to the cities of Britain, counselling them to look to their own defence.” The context for this comment is obscure; it comes in a passage describing the actions of a Gothic army at that time (summer AD410) rampaging around northern Italy, who had for a time besieged the emperor Honorius inside the walls of Ravenna and who were shortly to sack Rome itself. What did this have to do with Britain? The mystery has led several historians to conclude that Zosimus’s Greek text should actually read Brouttía or Bruttía (Bruttium, the toe of Italy) rather than Brettanía (Britain). But Bruttium is 500 miles away from Ravenna, and the Goths were marching in the opposite direction; why would Honorius be warning cities so far away, that were in no conceivable danger? Attempts to explain the name as Raitía (Raetia, roughly modern Switzerland) instead collapse on similar grounds.

*Ivory consular diptych of Anicius Probus, AD406, portraying the Emperor Honorius in martial guise. In reality, the young emperor had no experience of war.*

There seems, in fact, little reason not to relate this odd note to the passage shortly before in Zosimus’s history about the Britons taking up arms and throwing off the government of the usurper Constantine III. The letter, which was perhaps a rescript, or response to a petition, was addressed to ‘the cities of Britain’, which suggests that there was at that time no single leader or governor controlling the island, and that Britain had fractured into a network of individual power bases, perhaps centred on larger fortified towns like St Albans, Cirencester or Silchester; several of these, we might assume, had got together and addressed a petition to the emperor in Ravenna, requesting that he send troops to defend them and to re-establish proper imperial control over their island after the rule of the usurpers. Honorius, however, had his hands full dealing with Italy, and could offer only vain platitudes.

What seems clear from this interpretation is that Honorius was not telling the Britons that they were no longer Roman. This (in)famous letter was not a declaration that Britain was no longer part of the Roman empire. Nor, it seems, did the Britons themselves (or, at least, those who wrote to the emperor) want to cease being citizens of the empire, or for imperial rule over Britain to come to an end. Instead, these are rather desperate expedients by people whose options are limited and whose time is running out, trying to shore up the remains of a social and political structure and hoping that some lucky accident will deliver a way out of their malaise.

But there was no way out. By AD416 Honorius’s resurgent generals had crushed the rebellion in Gaul and ended the fighting in Spain, bought off the barbarians and executed the usurpers. But their military control did not extend beyond the Channel. The Rhine frontier remained too vulnerable, and Spain too fractious, for any concerted westward expeditions, and while the ‘cities of Britain’ may have come to believe that Roman rule would return to them some time soon, in the event it seems that no imperial military reinforcements, or any restored Roman civil government, ever set foot on the island after AD410. A handful of churchmen made the trip, concerned only to protect the Christian congregations of the island from pagans and heretics; that too was a losing battle.

*Surviving Roman fortifications at Portchester, a coastal fort originally built in the later 3rd century. The regular Roman garrison was probably withdrawn c.AD407*

Roman Britain had been an integral part of a vast interconnected empire, which brought wealth, technology, cultures and peoples from across Europe, North Africa and the eastern provinces. Once those connections were severed, urban infrastructure and local economy withered and died. Post-Roman Britain became a backwater, a landscape of abandoned settlements, crumbling buildings and subsistence agriculture, ruled over by feuding warlords. Trade links with continental Europe survived only in some places, and small amounts of Roman coinage found its way across the Channel too – some of it ended up buried in hoards, presumably to keep it safe in times of crisis.

As the beleaguered western empire staggered on through the violent 5th century, the Britons addressed plaintive requests to the Roman government and army to aid them in their distress. ‘The barbarians drive us to the sea, the sea drives us upon the barbarians,’ one letter, recorded by the churchman Gildas, groaned. ‘By one or other of these two modes of death we are either killed or drowned.’ But the Romans had their own problems, and could do nothing for distant ex-provinces any more. Within another century, most of what was once Roman Britain had fallen into the hands of Germanic rulers from across the sea, perhaps former warband leaders employed as mercenaries, now kings of a new Anglo-Saxon domain.

This, then, was the end of Roman Britain. Not a single violent upheaval, one gust of wind blowing out the lamps of civilisation, so to speak, but rather a slow fade of control and influence. The few short years of truculent rebellion, from 407 to 409, were followed by decades of decline, despair, and a steady unravelling of social, political and economic structures that saw Britain sink into a period of stagnation that would last for centuries.

It is quite possible that those living at the time of the slow sundering did not even known it was happening, and many of them would perhaps not concede for decades, even generations, to come that they were no longer Romans, and that the richly cultured empire they had once inhabited was gone for good.