Part II
Chapter 4
It is reasonable to speculate on the further unfolding of the history of the Weastern Empire as follows, bearing in mind the actual developments of society in the unconquered East and in the more urbanised areas of the West that survived under Germanic rule.
A kingdom of Britain
Decline in Roman military manpower in Britain in the later fourth century is probable, with many troops accompanying rebel Emperor Magnus Maximus to Gaul in 383. Indeed, later legend asserted that he had been the final Roman Emperor to rule in Britain rather than rebel Constantine III (who took a second army to Gaul in 407). Maximus allegedly settled a large force of British troops in Armorica, modern Brittany, led by his British wife Helen’s kinsmen. It is not clear how many troops remained in Britain after 383, but the frontier ‘limitanei’ forts on Hadrian’s Wall and anti-piracy forts in Yorkshire appear to have been garrisoned into the 390s. The departure of troops under Constantine III to fight the invading Germans in Gaul in 407 was a result of the central authorities in Ravenna failing to end an army to do so, as they had done in similar circumstances in the mid-270s and 350s. But a similar crisis leading to Roman troops abandoning Britain at a later date was probable, even had a competent Emperor (for instance a surviving Theodosius I) not needed to use British troops against the invaders of Gaul after 406. By the early 440s more tribes were moving into Gaul in flight from Attila, such as the Burgundians.
Assuming that the Empire had to withdraw troops and/or authority from Britain in the early fifth century to concentrate resources in Gaul, there would have been independent authorities in the island. Another Germanic crossing of the Rhine could still have required the Empire to order most of its garrisons in Britain to intervene, as the nearest large army, had the central government been preoccupied. Much is uncertain about numbers and precise tribal identities in the chaos of the early fifth century, but it is logical to assume that had aggressive and ambitious tribes (or tribal coalitions) like the Vandals been held back from crossing the Rhine in 406 the threat from the Huns would have led to a later attempt. The Western Roman civil war of 423–5 was an obvious opportunity to exploit military weakness, though that occurrence would not have taken place had the militarily capable co-Emperor Constantius III not died young in 421. Alternatively, a usurper in Britain could have taken most of his troops abroad and left the island’s provinces under-manned; Constantine the Great had launched his Imperial career from Britain in 306 and Magnus Maximus followed suit less successfully in 383. A rebel Emperor could have taken over Britain and defied the government successfully with his fleet, as Carausius did in 287–93.
Any of these events would thus have led to the British provinces breaking away from central control or being abandoned. But this did not entail an end to ‘Roman’ government in Britain. Roman-style civic institutions, with or without the villa economy, seems to have continued until the major Saxon attacks of the 440s (c.f. the Life of St. Germanus on the situation circa 429).1 The defeat of the German invasion of Gaul from 406, leaving the roads of Gaul more settled for trade and a Roman army on the Rhine in need of British corn, should indeed have aided the survival of the Late Roman economy and farming-system in fifth century Britain. The new states that emerged in post-Roman Britain, some at least dynastically based kingdoms in the tribal areas of the west and north, would still have been threatened by invaders in any scenario and had limited economic and military resources. Once the threat of Attila to the Empire passed around 453, Rome would have been able to lend assistance but it is not likely that any massive diversion of troops for a reconquest would have been seen as desirable.
It is debateable to what extent any British over-kingship in the fifth century owes more to medieval legend than reality. It is now argued that the stories of a powerful over-king during the post-Roman period that were current in the time of the first Welsh historian, Bishop Nennius of Gwynedd (fl. circa 829), were composed with a view to inspiring contemporaries about a British revival that the Bishop’s employer King Merfyn ‘Frych’ could lead. The legends of ‘Vortigern’, apparently the ancestor of the Kings of Powys in central Wales and the great war-leader ‘Arthur’ had a contemporary, ninth century purpose and should not be taken as an accurate record.2 The history of a powerful fifth century British kingship written in the 1130s by Geoffrey of Monmouth was certainly couched in contemporary, twelfth century terms that reflected Anglo-Norman kingship and its international pretensions, and is highly unreliable. But it is clear from the nearest contemporary writer, the monastic controversialist Gildas in the 540s, that the British civil and military authorities after 410 had fought back against the Saxons with initial success, which would suggest a unified command.3
Given the structure of Late Roman governance and military command (the latter is preserved in the Notitia Dignitatum of circa 400), there was a field-army under a ‘Count’ operating in Britain. Most of the troops seem to have left the island with the pretender Constantine III to fight in Gaul in 407, but the command structure could well have been re-created after 410 to co-ordinate resistance. Some modern historians, following Robin Collingwood, have argued that Arthur or his predecessor Ambrosius Aurelianus were Counts of Britain, utilising late Roman military structures.4 Novelist Rosemary Sutcliff duly used this idea.
According to Welsh tradition by the ninth or tenth centuries, the elusive ruler Constantine, possibly Custennin ‘Fendigaid’ (‘the Blessed’), who ruled before Vortigern, may have been called in from the expatriate British military settlements placed in Armorica under Emperor Maximus in the 380s. He could have been a son of Maximus, who had commanded in Britain before his usurpation in 383, or else a descendant of Maximus’ British brother-inlaw Conan Meriadawc of Armorica. In 1284 the conqueror of Gwynedd, Edward I, was shown the supposed tomb of Constantine, as son of Maximus, at Caernarfon – a late Roman military fortress in Gwynedd linked to Maximus in the Welsh poem ‘The Dream of Macsen Wledig’. The later Welsh genealogies placed Maximus, then a famous figure of legend as ‘Macsen Wledig’ (who starred in the twelfth century literary collection later known as the ‘Mabinogion’), at the head of several major dynastic lines including Powys and Morgannwg-Glamorgan.5 He was thus an important source of legitimacy to later British-Welsh royal court propagandists.
This may be due to later attempts to glorify the ancestry of important dynasties, but might genuinely reflect a real-life fifth century political role held by his Imperial descendants like Constantine. Some sort of supreme authority over parts of southern Britain seems to have been wielded by the elusive Vortigern (as indicated by his name, which means ‘overlord’), Maximus’ son-in-law, before the Saxon revolt which the Gallic Chronicle dates to 442; he and his Council called in Saxon mercenaries to fight the Picts and granted them land in the traditional Late Roman manner for ‘federate’ allies.6 After Vortigern’s overthrow leadership of the struggle against the Saxons passed to the ‘last of the Romans’, Ambrosius Aurelianus, of a noble Roman family wearing the ‘purple’ (would that have been consular or Imperial?) in the 470s or 480s (as stated by Gildas in De Excidio Britanniae in the 540s).7
The existence of a central military command for Ambrosius’ fight against the Saxons has sometimes been linked to the survival of the earlier Roman office of Count of Britain and of a Romanised cavalry force derived from the late Roman military tradition. Cavalry would have given the British the ability to move quickly around the country on the Roman road network, as has been implied from the wide ranging placing of the elusive Twelve Battles which Nennius ascribes to Arthur, and given them a military advantage over Saxon infantry. In fact the said battles may only have been ascribed to one man in later centuries, perhaps by ninth century mythographers. It is unclear if the office of ‘Count’ of Britain, or a similar command on the socalled Saxon Shore of southeast Britain centred on its fortresses, existed by around 400. The theory that the chain of fortresses from Portchester to Brancaster were the centre of a coherent, long-lasting Roman defensive network is also now in dispute; if they were military bases, where were their barracks? It has been suggested that the forts were probably more collection points for corn supplies en route to the Rhine army than major centres of troop deployment.8 It is more likely that they were mainly military. Whatever the true nature of the alleged network of Saxon Shore forts and the extent of Germanic raiding, the latter was evidently a major problem by the later fourth century, as were the descents of the Picts from modern Scotland and the Irish.
A triple attack and major destruction in 367–8 is testified to by Ammianus Marcellinus, and the few written sources for the early fifth century agree that the end of direct Roman rule in 410 was followed by another major attack which the Britons managed to fight off themselves.9 The local authorities who took action to raise troops, mentioned by Gildas around 540, would have been the civic councils of the major towns (principally the five ‘coloniae’) and presumably the senior civil servants of the five Roman provinces in Britain.
The names of the final civil governors (‘praeses’) and their military counterparts (‘duces’) in each of the five are unknown, but the complicated structure of late Roman civil and military governance would not have collapsed overnight and experienced officials and officers would have been available for the first years of independence. Given the pattern of urban and rural settlement, with farms rather than Italian-style villas predominant outside the South and Midlands and most towns in the lowland areas, it would seem likely that Roman cultural and economic life was essentially a phenomenon of the south and east, with traditional tribal ‘Celtic’ lifestyles predominant outside these areas. Even in this area pre-Roman tribal administrative terminology survived, e.g the name of the Cantii in Kent, and may underlie the geographical limits of later Anglo-Saxon kingdoms (e.g. Sussex as continuing the ‘Regni’, Wessex the ‘Belgae’ or ‘Atrebates’, and East Anglia the ‘Iceni’). Does this mean a survival of a sense of regional tribal identity by the local Romano-British landowners over 367 years of Roman rule, ready to emerge in 410?10 Did they even have identifiable aristocracies tracing their lineage to the conquered nobles of the first century AD? The pre-Roman names certainly survived in Roman Gaul, frozen into neat Roman administrative districts.
The division of Britain into two provinces, Northwest and Southeast, with capitals at London and York, by Septimius Severus, probably reflects the existence of a civil, romanised area and a military, tribalised zone. Noticeably, almost all the known post-Roman British kingdoms of the fifth century emerged in the latter; the Southern kingdom of Dumnonia, in Devon and Cornwall, had a non-Roman ‘Celtic’ pattern of farming.)
Continuing Roman authority in Northern Gaul through the fifth century would have been a source of backing to the post-Roman civil and military leadership, and possibly in the real-life chaos of post-406 Gaul the return of some degree of order after 418 may have resulted in a degree of Roman authority in or assistance to the more romanised areas of Southern Britain for a decade or so. (The term Celtic should be taken as referring to the indigenous pre-Roman Britons; the notion of a distinct culture or race’ is more contentious. The contemporary useage would have been ‘Britanni’; the term ‘Celt’ for Britons was invented by Edward Lhuyd circa.1690).11
There also appears to have been Germanic settlement in southeast Britain by the early fifth century, near towns and in undefended villages so by arrangement with the residents. This has been interpreted as a sign of Germanic ‘federates’ settled in Britain before the end of Roman rule, possibly to help defend the coast against other raiders from the Continent or seaborne Pictish and Irish raids. Many German artefacts have been found in the region near the late Roman Saxon Shore forts from Kent to Norfolk, leading to assumptions that the owners were German troops and their families based at these places. However, one modern theory prefers the idea that the presence of such Germanic artefacts need not mean German residents brought over from the Continent, only a shift in emphasis in trade from an insecure Roman Gaul to the Germanic lands, which brought in German goods. A change in imports and fashion, making Saxon ornaments desirable objects that the rich would then bury in their graves, is thus the explanation for the arrival of such items – not a mass-invasion of landhungry Germans.12 But the physical presence of at least some Germans is more logical, although Gildas’ ravings about massacres in mid-fifth Britain are dubious. If most post-Roman farms were left empty for new settlers as a result of Germanic attacks, why does the recently analysed vegetation record show no break in usage of the fields?13
If the Empire had still been extant and ruling in Gaul through the fifth and sixth centuries, Roman influence on terminology, military tactics, and institutions in Britain should have been much greater than in reality and a pro-Roman leadership in the campaigns against Saxons and Irish raiders would have been probable. In real life, by the 460s the only surviving Roman authority in nearby Northern Gaul was the kingdom of Soissons, the minor state based on the lands of Aetius’ former lieutenant Aegidius and then his successor Syagrius. This was practically independent after Aetius’ murder in 454 and the following year’s sack of Rome, and was conquered by Clovis the Frank and absorbed into his growing kingdom in 486. But had Roman power been sufficient to contain the Germanic invasions of Gaul after 406, as it had been in the 270s and 350s, the Empire could still have wielded authority as far as the Channel – except possibly for one or more allied kingdoms of Germanic tribal settlers in Belgica and on the lower Rhine, where Franks had been settled under their own leadership as early as the 360s.
The Roman Ambrosius, and his putative successor Arthur (if he existed), would have been bolstered by Roman support, and possibly mercenary troops, and a central kingship is quite likely to have evolved, held by the military warlords. Possibly other relics of Roman administration, not least the Church with its links with Italy, would have survived into the sixth and seventh centuries in a Britain that had driven out any invaders in the 440s and could look across the Channel for support and trade. The Romans’ fleets should have kept down piracy, and the larger Romano-British towns would have survived better provided that there was no widespread destruction by pirates or a catastrophic decline in trade due to insecurity.
Accordingly, there would have been Roman assistance to an independent Romano-Celtic kingdom of Britain in the sixth and seventh centuries under a line of successors of the Count Ambrosius Aurelianus (maybe including the mysterious commander later known as Arthur, the Celtic for bear) This state would have evolved directly from the Roman provinces of romanised Southern Britain, and would be run by a mixture of civic officials and a landed nobility. Conceivably some of the more self-sufficient villas might have survived as functioning economic units, with a powerful local landed class as in post-Roman Gaul. The real-life collapse of the villa economy in Southern Britain is now put down to the end of their economic viability, as providers of large-scale agricultural produce for the Western Roman government and army, rather than systematic destruction by bands of Germanic marauders.14
Thus, a continuing demand for British corn (e.g. from the drained Fenland or former great Imperial estates) for the Roman army on the Rhine, and a secure, brigand-free network of roads across Gaul should have enabled the majority of villa estates to continue functioning through the fifth century. The most probable scenario for a rural crisis and economic decline would have been the loss of agricultural manpower, and markets for produce, in the great plague of the 540s, which according to surviving British and Irish sources afflicted post-Roman Britain badly.15 It presumably spread via the trade routes, archaeology showing that there were Mediterranean imports to southwestern Britain via ports like Tintagel and Bantham, and would have been worse in a politically stable Western Roman state where trade was still at the levels of around 400. As in relatively peaceful late sixth century southern Gaul in real life, post-Roman towns and estates would have been badly affected by plague and at risk of decline.
There might be independent but allied tribal kingdoms in the hillier zones of Northern and Western Britain that did not have Romanised towns or a villa economy, without loss of territory to Saxon and Irish settlers. From archaeological evidence, the latter seem to have been locally predominant in Cornwall, Pembrokeshire, and the Lleyn Peninsula in the early fifth century. The written evidence of later genealogies for the ruling dynasties of the emerging fifth century kingdoms has to be treated with caution, given that our extant information is as late as the tenth century and was compiled retrospectively for the descendants of those new kingdoms that had survived that long. Heroic saga may well have magnified, or outright invention falsified, the oral record remembered by bards at Royal courts. Later heroic mythology has been accused of inventing the whole saga of the founder of the Anglo-Saxon kingdom of Kent, the mercenary captain Hengest (whose name means Stallion), as well as magnifying or inventing the deeds of the British war-leader later identified as King Arthur who by the tenth century was supposed to have brought Ambrosius’ Saxon war to a victorious end at the battle of Mount Badon around 516.16 The same problem could apply to any dynastic founder or early ruler only known to us from written accounts centuries later.
Our nearest source, the monk Gildas around 540, deals as much in inference or allusion as in fact in his polemic against the sinful British leadership of his time. But he names one of the five rulers he condemns, Constantine, as king of Dumnonia; the others are mostly identifiable from the genealogies, e.g. Mailcunus (Maelgwyn) of Gwynedd, Cynglas of Powys, and Vortipor of Dyfed.17 (The latter’s memorial-stone has survived, giving him the late Roman military rank of ‘Protector’). Other basic information vital to post-Roman history is uncertain; we have no clear idea of whether the Lothian prince Cunedda was called into Gwynedd to evict Irish settlers by the Roman government around 400 or by a later ruler (could it be Vortigern?) around 440. The claim that he arrived ‘146’ years before the time of Maelgwyn, who died in the plague of around 547/9, is at variance with the later Welsh genealogy which ascribes only two generations from Cunedda to Maelgwyn’s father Catwallaun.18 The terminology that Gildas uses for his tyrant kings implies that they were illegitimate rulers, i.e. not legally appointed magistrates or governors but self-appointed war-leaders.19 This is presumably the view of a legalist churchman of new men warlords flung up by military emergency.
Kingdoms that had been absorbed into other polities may well have left no record, and there is minimal information in the tenth century genealogies on the rulers of those lands absorbed by the new Germanic kingdoms of lowland Britain in the sixth and seventh centuries. Many rulers of lowland states may have been left out of the record because they left no heirs to preserve their details. Gildas makes it clear that tyrants, i.e. rulers lacking legal and legitimate authority, had sprung up all over Britain by his time, and he refers to some kings, e.g Aurelius Caninus or Conan (of Gloucester?), and dynasties (such as that of Ambrosius) which are not referred to in extant Welsh genealogies. Our picture of post-Roman government in Britain is thus partial and probably inaccurate.
Continental developments
Likely offensives with Rome’s Germanic allies would have taken place to keep the Saxons in check by attacking them in the rear by land and along the North Sea coasts by sea with the continuing Classis Britannia operating from the Saxon Shore forts and Gesoriacum (Boulogne). If sufficiently Romanised, the Germanic tribes east of the Rhine could aid a Roman conquest and settlement of the Saxon territories; it would have been useful to utilise the energies of warlords such as the emerging Merovingian line of the Franks to fight for Rome so they did not gain their loot and prestige from attacking the Empire. The land hunger of the Angles, Saxons, and Jutes trapped in the coastal areas along the North Sea coasts from Frisia to Jutland (which in reality led to a migration to Britain, though of disputed extent) would have been blocked from British ventures by a strong resistance in the island. Similarly, the stronger position of the Western Empire would have meant that peoples such as the Franks were still living in the romanised areas east of the lower Rhine and would have blocked expansion in that direction. As a result, warfare with Rome leading to their military defeat on land and sea could have meant that many of them would have been enlisted in the Roman army and acquired land across the Empire on their retirement rather than forming their own political authorities under their own leaders.
The Empire could have Christianised them and used them as ‘federate’ Germanic allies in Roman expansion east of the Elbe. There had been Christianization of Germans beyond the Roman frontier in the earlier fourth century, by Ulfilas among the Goths, though it is unclear if his initiative was taken with backing from the civil or ecclesiastical leadership with a view to the strategic advantages of it. As he was an Arian, not a Catholic, in theology this resulted in major problems for fifth century Arian Gothic kings in dealing with the Catholic bishops of their new kingdoms. In real-life Gaul around 420–30, it appears that the local episcopate, maybe with Papal backing, saw the potential in firstly Palladius and then Patrick taking on missions to convert the heathen and hostile Irish.20
Accordingly, some similar mission might have been mounted by zealous clerics within Gaul or the Rhineland to convert German tribes beyond the Roman borders. The existence of a single, charismatic leader in new kingdoms, such as the Salian Franks’ real-life rulers Childeric and Clovis, would have presented a tempting target for conversion, though there would have been less urgency if such men had not been ruling Roman Christians within the old Roman frontiers. Even if the Franks had been blocked from expanding in Gaul after around 480 by the Roman military authorities, and thus driven to attack fellow-Germans in the lower Rhine valley, converting their leaders would have been politically useful in cementing an alliance. The see of Rheims took the lead in working with Clovis in real life, and in this scenario would still have been geographically close to the Frankish kingdom so with an interest in ensuring that Clovis was an ally who did not raid fellow-Christians in the province of Belgica
Quite conceivably, the Western Empire would have gone on in the seventh century to annex Jutland to prevent any further raids across the North Sea. The peninsula appears to have been divided among small tribes, traditionally the enigmatic Jutes, Angles, and possibly some Saxons in Schleswig, without major kingdoms in the real-life fifth to seventh centuries, apart from possibly the realm of the original king Offa of the Angles whose descendants ruled Mercia in England. Without a major settlement in England from around 440 there might have been overcrowding in the peninsula, or else hardship in the coastlands arising from flooding due to rising sea levels, both matters of historians’ speculation.21 Without a safetyvalve for settlement overseas many more warriors might have enrolled in the Roman army for betterment, or aggressive war-leaders been as much of a menace to the Roman lands on the lower Rhine as they were to Frankish Austrasia ahead of Charlemagne’s conquest in the 770s. Any continuing raiding into Roman lands would have made retaliatory invasion logical, assuming that the traditional Roman option of paying and supporting friendly tribal leaders to preserve peace on the border had not worked in the long term.
Jutland would logically be divided up among farmer-soldiers (some locals and some veterans) to form a Western equivalent of the Eastern ‘theme’ armies. The settlement of farmer-soldier ‘limitanei’ on the frontiers of Eastern and Western Empires after the late third century, providing a backbone of locally based men with military experience to support the field armies, would probably be continuing into the sixth or seventh centuries if the West had survived. It was ideally suited to utilising the social basis of society beyond the western frontiers, namely Germanic warriors used to both farming and fighting, for defence of new territories under Imperial politico-military leadership. Beyond the neutralised peoples of the Danish peninsula, loyal vassal-kings would be assisted by trade and military help against their rivals in Scania and Geatland (southern Sweden). The Danish and Geatish peoples had local kings by the sixth century if the later legends written down about their royal families are to be taken with any degree of accuracy. The later Danish historian Saxo Grammaticus wrote of the ‘Scylding’ dynasty, the people of Scyld, in Denmark,22 while the famous (possibly eighth century) heroic poem ‘Beowulf ’, its events dated to around 500 by the timing of a reference to a historical attack on Gaul, refers to king Hrothgar of the Danes and the eponymous hero, King Beowulf of the Geats.23The mythic events of the saga, with their lake-monsters and dragon, are clearly invented, as are the tidy back-construction of a long-ruling dynasty in Saxo’s work. But, as with the British myths of King Arthur, their usage of legend and contemporary references may well hide a kernel of truth about the antiquity of kingship, though not a full, national dynastic kingdom, in the area.
As with the Roman promotion of trustable leaders beyond the frontier with Roman goods and backing to keep their turbulent peoples in order in first to fourth century Germany, the Empire would logically have served to promote kingship and stability among its Northern neighbours. Christianised kingdoms on the periphery of the Roman world would thus have evolved in Sweden and any unconquered part of Denmark at an earlier date than they did in reality, sponsored by the Empire and the Church to aid stability on the frontier. But a similar development in the divided jarldoms of pre-tenth century Norway is less likely, as the intensity of feuds among the warrior-nobility and lack of a clear dynastic authority seen in the sagas would militate against stability. Christianization or diplomatic relations with a powerful ruler may well have occurred but proved impermanent, as with the Frankish empire’s attempts to sponsor Christianity and stability in Denmark after around 800.
The Roman fleet, if indeed there was one, based at the supposed Saxon Shore fortresses in Britain in the fourth century had failed to hold back Germanic or Pictish raids, possibly because the invaders’ long keels were superior to Roman shipping used to the Mediterranean (perhaps using sails more than oars) or because their small groups of fast-moving vessels could elude Roman patrols. The only late Roman admiral in the Channel with a successful anti-pirate record that we know of was Carausius in the 280s, and he was accused of keeping the arrested pirates’ loot for himself and revolted to escape punishment.24 But it can be assumed that the Romans would have had to master North Sea tides and storms to tackle the Danish coastline successfully during an invasion of Jutland, and to stave off further raiding on the British and Gallic coasts. An invasion of the mainland would leave searaiders with no refuge unless they escaped beyond Roman reach to Norway or the Baltic, and it would be logical for the empire to take on seaborne as well as land-based German-Danish mercenary ‘federates’ and reinforce its fleet with local experts. Roman naval bases around the sites of Bremen and Hamburg would police the North Sea’s eastern shores and the Skaggerak, aided by new military and naval bases around Aarhus and the Danish islands, and it is likely that the Church would seek to Christianise the area (as with hostile pagan Ireland) and set up monasteries as beacons of ‘Romanitas’.
Ireland
The Church in Rome had sponsored the civilising missions of Palladius and Patrick in the real-life mid-fifth century. If the Western Empire had continued, Rome’s interest in the project would have been greater (not least to discourage local raids on Britain and Gaul) given that the post-560s Papacy would not have been distracted by its local political role in Italy as it was in real life. The main centre of administrative expertise and organisation in the senate-less Rome of the restored Imperial Italy from the Gothic defeat in 553/4, it had an important local role backing up the civil government (which was based across the Appenines in Ravenna). The mixture of plague and devastating war had reduced the personnel available to man the administration of Italy, and from 568 the region was afflicted by a piecemeal penetration by bands of Lombards who were centred in the Po valley but by the 570s and 580s were spreading further south. The lack of a concerted invasion by a powerful Germanic army, as with the Goths in 402, 405, and 408, or of a permanent centralised Lombard war-leadership did not prevent the Lombards from serious disruption. Assorted local duchies were set up usually with autonomy from the emerging Lombard kingship based at Pavia by the Po; a major one was at Spoleto in Umbria, within striking-distance of Rome.
The estates of the remaining Roman nobility and the Papacy were being raided, thus diminishing their resources, and Rome itself was threatened by the time of the reign of Pope Pelagius II (579–90). The Lombards were a major preoccupation for Gregory the Great and his successors. A stable and peaceful Imperial government in Italy would have avoided this distraction and enabled the better-resourced Papacy to concentrate on useful missions like converting the Irish to aid the Empire’s foreign relations. Conversely, however, the political and military weakness of the Eastern Empire’s viceroys in Italy, the ‘Exarchs’, and the absence of the Senate meant that the Papacy had to assume local civil leadership in central Italy. Lacking this stimulus to its administrative development and initiation of its own foreign policy, the post-550s Popes would have been less powerful than Gregory and his ilk, and under closer Imperial control even if the Western Emperor still ruled from Milan.
The emerging Christian Church organisation across Ireland would have received more aid from Italy had the central Church authorities had more resources. Patrick is unlikely to have been the only (recorded) mainstay of the conversion-mission, and the Church in Britain or Gaul would have been directing his mission and supplying priests. It is also probable that local customs at variance with those of the Roman Church, the different form of the priestly tonsure and the divergence in the date of celebrating Easter, would have been slower to develop, if they had done so at all. In real life the Church in Ireland and its offshoots, including Aedan’s mission in post-634 Northumbria, was allowed to develop without a stream of instructions delivered by zealously conformist officials sent from Rome.The result was a major divergence in practices which provided inconvenience, though not any theological split between a (supposedly more liberal) Celtic Church and Rome as some anti-Catholic historians have interpreted this problem. As Rome asserted its influence in Celtic-influenced Christian lands in the midlate seventh century, commencing with Britain, it made efforts to enforce its own agenda and practices.
Thus the representatives of the two parties in the Church came to argue out their cases before the civil leadership of Northumbria at the synod of Whitby in 664, with Rome’s representatives led by St. Wilfred winning; the clinching argument was the role of Rome as heir to the senior apostle St. Peter, at least as Bede recorded it.25 The triumph of Roman practices in the morer remote Dalriada and the Pictish lands in Scotland, let alone in Ireland itself, had to wait until the eighth century. A surviving Western Empire would have provided the political weight, and probably the greater Roman missionary manpower, to bring about earlier submission to the Papal practices, though the 540s plague and local military preoccupations might logically have delayed efforts to bring Irish and Scottish missionary Churches into line with Rome.
The Empire would also have been keen to aid civic order and a central control over potential raiders from Ireland. It had backed up centralised rule by pro-Roman leaders to control their warlike inferiors on the Rhine and in Britain in the early empire, as well as making these alliances with local kings the mainstay of its eastern Mediterranean and Middle Eastern foreign policy from the late Republic onwards. For a start, it was cheaper than annexation. As has been seen earlier, it is probable that Valentinian I (via Count Theodosius) resorted to this expedient beyond Hadrian’s Wall after 367. Indeed, it was late Roman practice to build up supposedly controllable and Romanised kings to control the threatening Germanic peoples, including Alaric as the Gothic ruler before 395. The Irish were part of the coalition that attacked Britain in 367, whether or not any High Kingship existed at that time to direct raiding, and the archaeological evidence shows that they were settling in the Lleyn peninsula, Pembrokeshire, and Cornwall in the fifth century. The traditional Dyfed royal pedigree linked the southwest Wales Irish leadership to the royal house of Leinster.
Backing a pro-Roman kingship in Ireland, or at least in provinces whose inhabitants were raiding Britain, in the fifth century would have followed normal practice. According to John Morris’ theory, the British ruler Vortigern’ of the 430s established this sort of link with the ‘High King’ Loeghaire.26 Thus a surviving Western Empire would have seen the value of supporting the fifth and sixth centuries High Kings of the ‘Ui Niall’ dynasty, at least once the threat posed by Attila had passed and such alliances could be considered at leisure. This is subject to the caveat that we cannot be certain how powerful the High Kingship based at Tara-Temhair actually was in the fifth and sixth centuries. Did it really establish a form of control or leadership of the sub-kings of the Five Provinces, or was its real power restricted to the eastern province of Midhe where it was based?
It was subsequently claimed that the line of Niall ‘of the Nine Hostages’ (d. 405?) had been powerful over-kings until the eclipse of the central kingship in the 550s, when a coalition of provincial rulers aided by St. Columbcille (Columba) brought down Diarmait mac Cerbhall and reduced his successors to nominal national power. But modern historians would prefer to contend that the centralised power of Niall’s line had always been ephemeral beyond the plains of central Ireland and the kingdom of Midhe. Their alleged control of their allies was an anachronistic myth promoted by tenth and eleventh century writers who wanted to look back to a Golden Age of royal power.27 The Church, too, found it useful to claim that one centralised kingship had served as the ally of the national apostle St. Patrick, thus presenting a template of secular-religious co-operation for later kings to follow. Did later writers create the myth of a powerful fifth century High Kingship for contemporary rulers to follow, as they undoubtably exaggerated, or maybe invented, the earlier kingship of the Golden Age of Cormac mac Airt in the third century?
It is possible that a Roman military expedition would assist a pro-Roman client High King in defeating his rivals and becoming a reliable ally in return for aid in ending all raiding on Britain. This political and military support could have proved crucial in mid-sixth century High Kings of Niall’s line in resisting their dynastic and provincial enemies successfully, and securing domination for their kingdom of Midhe over its neighbours with the aid of Roman troops and/or weaponry. The Roman Church could order its local Catholic bishops to assist the King and promote the kingship’s role, as in seventh century Britain. As in reality, tribal dynastic families would provide a number of the leading clerics; powerful abbots would gain land and influence for their monasteries. But a Roman-influenced British state(s) and Church would still be in existence across the Irish Sea, and British clerics would play a part in encouraging the Irish Church to develop on Roman lines (e.g. adopting the Roman dates for Easter). Ireland did not have towns to serve as the seats of bishoprics in the Roman manner, however, so a Roman pattern of urban sees could not develop; the bishops would still have been attached to the tribal royal courts.
Thus it is possible that in the crucial confrontations around 560 Diarmait mac Cearbhall would have prevailed over decentralising provincial rivals, not least St. Columba and other Ui Niall princes, and preserved the High Kingship as a strong force for the coming decades. It is less certain that a hereditary kingship could have emerged, due to the comparative strength of the provincial under-kings who would have resisted that. A dynamic ruler would have had to establish a centralised army to enforce his will, possibly with Roman or British mercenaries. The main provincial kingdoms of Leinster (under the two rival lines of the ‘Ui Dunlainge’ and ‘Ui Cennselaig’), Munster (under the descendants of the mid-fifth century king of Cashel, Cormac Corc), Connacht (under the family of mid-fifth century High King Aillel), and Ulster (under a branch of the ‘Ui Niall’ based at Ailech), should have survived as the main political units, with a mass of minor local tribal kings. Unless the Roman Empire had annexed southern Scotland permanently, under Agricola around 80–4 or Septimius Severus in 208–11, the lands of Argyll (‘Coast of the Gael’) would still have been available for settlement in the fifth and sixth centuries by eastern Ulster peoples pushed out of their homeland by the ‘Ui Niall’. The Irish settlers’ kingdom of ‘Dalriada’ would thus have evolved as in reality, though a powerful central British kingship ruling to Hadrian’s Wall would have restricted southern raiding or conquest by them or their Pictish neighbours.
Dalriada and the Irish overseas
It has been suggested that the post-367 Roman military recovery in the North involved setting up pro-Roman border kingdoms of Celtic allies in Strathclyde and Lothian (Gododdin) to block Pictish raids, as implied by the Roman names of their alleged dynastic founders (maybe Clemens and Paternus) and late fourth century dating.28 Lothian had a strong military tradition, with its prince Cunedda being called South to drive the Irish out of Gwynedd (in 400 or 440?) and a famous heroic campaign led by its warriors against the invading Angles at ‘Catraeth’ (Catterick?) around 600 commemorated in the poem ‘The Gododdin’.29 If so, a strong post-Roman authority in Britain should have been able to assist these kingdoms as a buffer to Pictish and Dalriadan power. Alternatively or in conjunction with this, Roman Church missionaries would have sought to convert the Pictish and Dalriadan kings to Christianity and to make them reliable, non-raiding Roman allies. An imposition of central control and order on Ireland by a pro- Roman dynasty in the fifth or sixth centuries would have encouraged those chieftains and warriors who did not wish to co-operate to emigrate to free Argyll and bolster the manpower of Dalriada. An ambitious Irish princely missionary like St. Columba would have been a logical choice for the Roman Church to use in converting his fellow-Irish-speakers in Dalriada.
Lacking the large-scale legionary forces to hold down both Ireland or the Saxon-Jutish lands in the long term, the Empire would naturally co-opt the missionary zeal of the Church to civilise its potential enemies as the figures in the actual Church did with lands beyond the fifth and sixth century Christian frontier (Ireland, Anglo-Saxon England, and the Goths) in reality. The military power of the Empire would help to tie the new bishoprics in Ireland and Denmark into the fabric of the Western Imperial Church administrative system. But in semi-independent vassal Ireland, local tradition would assist in the continuing evolution of powerful monasteries rather than urban-based bishoprics as the centres of Christian civilization.
In real life, the Irish clerics provided a major stimulus of manpower and enthusiasm for re-converting Western European lands that had once been Christian but had now reverted to Germanic paganism. They were active across both Britain in the sixth century and newly Anglo-Saxon England in the early-mid seventh century, as hagiographies and Bede’s account make clear. In due course they moved on to Gaul, with St. Columbanus’ mission extending as far as modern Switzerland. Had the Western Empire survived, southern Britain and Gaul as far as the Rhine would have remained Roman Christian through these centuries. But the Roman Church had shown little or no interest in converting the Germans beyond the Imperial frontier in the fourth and fifth centuries, the crucial Arian mission of Ulfilas to convert the Danubian Goths came from Constantinople and there was no equivalent on the Rhine. Would the missionary zeal of the wandering Irish monks have led to missions beyond the Western Roman frontier in central Europe?
One logical target for conversion would have been the Saxon peoples, fiercely devoted to paganism on the Continent in real life until Charlemagne the Frank sought to convert them by the sword in the 770s and chopped down their sacred tree Erminsul. Their central German neighbours had been converted earlier in the eighth century by Germanic-speaking Saxons from England, led by St. Boniface. If the Anglo-Saxon migration to Britain had not occurred, the real-life political leadership of their kings, who sponsored the Church in seventh England, are unlikely to have emerged to provide invaluable backing to such missionaries. As Bede makes clear, the adherence of the local king to conversion was crucial to its success; where a new king returned to paganism, as several times in Essex, and nearly in Kent in 616/17, the mission faltered. But as far as can be judged it was the political and military needs of the new Germanic polities in Britain which gave the real-life Anglo-Saxon dynasties the opportunity to emerge. On the Continent, the only royal line to have held any sort of prestige or power was that of Mercia’s ‘Icelingas’ under shadowy rulers such as Offa of Angel. If the patriotic Danish historian Saxo Grammaticus was using genuine tradition in his later accounts, there may also have been Danish overlords for zealous Christian missionaries to approach.
Western Christianity – Emperor and Pope
A Roman Emperor ruling in Italy would necessarily have meant that the Church in Rome of Gregory the Great’s time was more like the real Church in Constantinople, submissive to the politics of the Court and theological whims of the Emperors. But the solid Catholic theology of most of Western Europe means that once Arian German rulers had been persuaded to recant by Imperial military power under a concerned Emperor, in this scenario probably Justinian after 536/40, it is less likely that Western Emperors would have sought to interfere theologically in high Church politics as the Eastern rulers did in the sixth, seventh, and eighth centuries. Without the usurpation of local power by an Arian German tribal elite, the leadership of the West would have continued to be Catholic. Catholicism had been unchallenged as the dominant Western theological doctrine at Court since the end of the Arian regency of Justina for Valentinian II in Italy (375–87), when Bishop (St.) Ambrose of Milan had earned heroic status for defying her attempts to assist her co-religionists. The final pagan Emperor had been the usurper Eugenius in 392–4, and even then the alleged assault his regime had launched on the Church was probably exaggerated in retrospect by his defeaters.30
The triumph of Catholicism and creation of one state doctrine had then been finalised by Theodosius I, with his legislation against pagan temples and worship accompanied by similar orthodox moves to marginalise Christian heresy. Any residual sympathy for pagan religious practices, apart from rural conservatism in customs, would have centred on the pull of centuries of tradition, and the good luck pagan religious observance had brought the Romans, among the aristocracy. The latter had led religious observance in the annual round of ritual observance in Rome, due to monopolising the priesthoods, and their conversion to Christianity was clearly a gradual matter over generations despite official legislative prodding by zealous Emperors, principally Theodosius. Pagan resentment of the latter had played a part in the revolt of 392–4, in which great aristocrats like Nicomachus Flavianus had had a leading role, though it has been exaggerated. The cause of the ‘Altar of Victory’ in the Senate House, whose removal on Imperial orders was resisted by leading aristocrats in the 380s, was an example of the physical separation of the worlds of the Senate and the (non-resident) Christian Emperors.31Most of the Senate appears to have adapted to the new religion during the early fifth century and the ban on old rituals enforced the change of the old Rome to the city of Ss. Peter and Paul, but the survival of the Senate would have aided the notion of a traditional aristocracy at a distance from the Court.
The new attacks on official doctrine about Grace and Predestination by Pelagius in the early fifth century had never been popular enough with those possessing influence in court or in the clergy to stand a chance of Imperial support and protective legislation, and had eventually been banned after intensive orthodox lobbying. In the East, in contrast, the rival Nestorian theology had been a serious threat around 430, with a risk of Imperial backing from the easily influenced Theodosius II who shortly before his death (450) took up Monophysitism. His sister Pulcheria quickly re-asserted Catholic control of State Church dogma and office in 450–1, but two further Emperors backed the Monophysites, Basiliscus in 475–6 and (tentatively) Anastasius in the 500s, causing orthodox revolts. The Monophysites remained predominant in Syria and Egypt, and Justinian was apparently on the point of enforcing his own third way to reunite the two hostile dogmas when he died in 565. He would probably have infuriated both parties and achieved the hostility of both. Heraclius and Constans II attempted a similar theological reconciliation by Imperial fiat and doctrinal innovation in the 630s and 640s. But this problem did not exist in the West, where even Pelagianism only seems to have been rampant beyond the Imperial frontier, in Britain, if Constantius’ nearcontemporary life of St. Germanus is to be believed, by the 430s.32 Catholicism would have maintained a theological dominance aided by State power, and it is unlikely that a Western Emperor would have been keen to support an Eastern Monothelete or Iconoclast enthusiast by calling a Church council to change Western doctrine in his support.
Eastern Orthodox theologians offended by their Monothelete or Iconoclast ruler’s heresy would have been likely to call on a Catholic Western Emperor to invade and depose the blasphemer, particularly determined persecutors such as Constans II in the 650s, Constantine V in the 760s and 770s, and Theophilus in the 830s. It is not impossible that an ambitious adult Western Emperor with no pressing military problems and hopes of unifying the Empire would have listened to them, though two of the three most determined Iconoclast Emperors (Constantine V and Leo V) were good generals which would have discouraged this sort of adventure. Bearing this threat in mind, the Eastern Emperors would have been likely to secure their Western counterparts’ neutrality before embarking on major doctrinal changes, and the practical requirements of military alliance against the Arabs between the Empires in all doctrinal controversies.
The Western Emperors might well have intruded court favourites into the Papacy, although the absence of the Emperors from Rome made their interest in the state’s principal see less than was occurring in contemporary Constantinople. Constantius II was the only fourth century Emperor to actively interfere in papal appointments; the see of the Court residence, Milan, was more at risk. Imperial nominations to sees of the fourth century had been stimulated by a need to support the Emperor’s own doctrine against its rivals at a time when the Catholic victory over Arianism was not assured, as seen in Constantius’ and the regent Justina’s Arian appointments and Theodosius’ Catholic reaction; this conflict was now over. But an Emperor with interests in theology or Church personnel would undoubtably have interfered with Church promotions to favour their own court candidates, at least in areas close to the Imperial residences.
A great Roman aristocrat with diplomatic experience such as Gregory the Great would have been a natural choice as Pope in 590, but he would have had less of a political role as there was still an Emperor in Rome, Ravenna, or Milan and and there would be no Lombard invasions of Italy. An ambitious and talented Pope such as Gregory would have been more of a court adviser like Ambrose of Milan in the 380s, encouraging the Emperor against heresy and able to send out more missionaries (e.g. to Saxony, Denmark, and Dalriada and Pictland). But whether the Emperor was resident in Rome, Ravenna, or Milan the Popes would have been under his eye and incumbents who defied his wishes would have faced the deposition which Constans II inflicted on Martin I in 649 for opposing the ‘Type’. In real life the weakening Imperial power in Italy led to Pope Sergius defying attempts to evict him by Justinian II’s troops, the arresting officer allegedly had to hide from the Rome city mob under the Pope’s bed, and in the eighth century the Popes defied Iconoclasm openly.33 This divergence between Emperor and Pope added to Imperial inability to defend Rome from the Lombards, and led to the Papacy calling in the Carolingians from Francia as its new, Catholic military ally from 751. This would have been inconceivable in a continuing Western Empire with an Emperor still resident in Italy.
There would certainly have been no succession of disreputable ninth and tenth century Popes set up and deposed by noble factions in Rome with accompanying poisonings and massacres, as the city would have been under continuing strict Imperial governance. At the worst, there would have been factional intrigue and rioting on the occasions of disputed Papal elections when the Emperor was preoccupied elsewhere, as in the 360s. The continuation of the great Senatorial dynasties of the fourth and fifth centuries, now fully Christianised, could have led to the sort of struggle between them over the Papacy that occurred between similar wealthy Roman dynasties in the fourteenth to seventeenth centuries, at least when the Emperor was not sufficiently interested to impose his own candidates. The later Orsini, Pamphili, and Barberini Popes would have had their dynastic equivalents; the most powerful and wealthy dynasty of fifth century Rome was the Anici.
What of secular power and influence in Rome? The great dynasties survived the collapse of the Western Empire in real life, with the Senate functioning, and consuls being appointed, under Odovocar and Theodoric. The Gothic kings had adopted a Roman court lifestyle and titles and continued to be advised by great Roman aristocrats, most famously by Cassiodorus and the executed philosopher Boethius. Ironically, it was Roman reconquest not Gothic rule that fatally damaged their world, as the Gothic army managed to recover from its defeat by Belisarius in the 536–40 campaigns and launched a fight-back under Totila that led to Italy’s devastation. This commenced before the great plague and the combined threats of Persia and Balkan raiders had already caused Justinian to reduce his military commitment to Italy by 542, but the loss of manpower and revenues in the epidemic made the war longer and more ruinous. The Senate seems to have ceased functioning in the 540s as a result of the dislocation and flight caused by the Gothic wars, when Totila captured Rome and drove out the inhabitants in 546. The landed aristocracy and many rural estates were ruined; this would not have occurred in a continuing Western Empire without a Gothic war, or in an uninterrupted Justinianic reconquest. Justinian’s suspicious character and alleged miserliness, made much of by the savage pen of Procopius in the ‘Secret History’, hindered the Empire’s ability to tackle Totila, or contemporary rebels in North Africa, quickly in the 540s.34 But without adequate manpower, or money to hire Germanic or nomad mercenaries if the Empire was short of troops, even a fully-trusted Belisarius would have had to rely on luck and his strategic genius to kill Totila and wipe out his main army quickly and limit the damage to Italy.
Monasticism would have continued to grow in peacetime, but with more secular careers open to ambitious and/or literate civilians it would have attracted fewer able candidates and it would have had to rely on Emperors and local landed aristocrats for donations of land and money. It would not be the only centre of learning, as a continuing urban Roman society would have kept secular schools open. In real life, many leading aristocrats in Gaul and Italy chose ecclesiastical careers after the fall of the Empire, there being no functioning bureaucracy in the post-Roman German kingdoms and civil government now being under the control of a German elite. Towns in the more Romanised south of Gaul fell under the leadership of aristocrats of ancient lineage as the local bishops, and their dynasties monopolised the senior clerical offices (c.f. Gregory of Tours’ family).
This would not have occurred had the Empire continued. Estates were transformed into monasteries by devout aristocratic laymen, such as Cassiodorus in Italy; this phenomenon was underway already before the end of the Empire, as seen by the career of Paulinus of Nola, but if the Empire had continued it would have been one among many options. Certainly the sense of a world coming to an end in invasion and chaos, which benefited the otherworldly preoccupations of the emerging monastic movement, would not have been so strong had Imperial government continued. Monasticism was well underway across the West by around 400, e.g. at Lerins and Tours in Gaul, and would have continued to exert a pull for devout Christians, but would probably have had fewer adherents. The absence of major wars in Italy in the sixth century, though not the absence of plague, would probably have given St. Benedict fewer recruits, and arguably a great Roman noble like Gregory would have had less certainty of following a Church career.
Military matters
There would have been less risk of a major barbarian threat to Roman military power in northwest Europe in the seventh or eighth centuries, a period of relative stability between the major movements of Germanic peoples in real life. The caveat here is that a Western Roman military block to westward and southward Germanic incursions in the period after 406 would have prevented the emergence of at least some of the emergent German-led kingdoms of the real sixth and seventh century, most notably the settlements in Spain (Vandals and Suevi from circa 410, and later Visigoths from the 460s), Italy (Ostrogoths’ and their allies from 476/93 and later the Lombards from 568), and Africa (Vandals from 428).
The pressure of Attila’s empire on the peoples of Germany in the period around 433–52 might well still have led to the Rhine frontier being overwhelmed by refugees then, and to a surviving Western Roman ‘comitatus’ under Aetius after 454 having to accept Germanic peoples west of the Rhine. But a still militarily powerful Western Roman state, with a larger and better-equipped army than the disunited tribal forces ranged against it, would have kept the Empire in the militarily favourable position of Theodosius’ forces around 395. The Empire would have been likely to cede control of northern Gaul and the lands from Upper Danube to Alps as indefensible, leaving them open to the creation of Germanic kingdoms (logically created by the real-life fifth century founders of new states such as Gaiseric, Athaulf and Wallia, the Goths, and Theodoric). Given a lack of ruinous civil wars, the inner provinces should have remained under Roman control, and the new Germanic kingdoms would have been the Empire’s inferiors in resources and military strength.
The Empire had already adapted to the presence of coherent barbarian polities and armies within its old frontiers, with Theodosius’ rapprochement with the undefeatable Goths in Thrace after 381; and Stilicho was able to hold back and make use of Alaric in the period 395–408. Indeed, as a fellow- German he was to be accused of being suspiciously unwilling to destroy Alaric when he had the chance.35 Similarly, Aetius was able to use the Gothic kingdom of Toulouse and other Germanic states and warbands in Gaul as his junior allies against Attila in 451. Logically, a stable Western Roman polity in the fifth, sixth, and seventh centuries would have preserved this favourable political and military position with regard to its new neighbours. Had the Rhine frontier been preserved by a line of long-lived and vigorous Roman commanders (Theodosius, Stilicho, Constantius III, Aetius, and perhaps Majorian or Aegidius) the Germanic kingdoms would then have emerged within Germany to its east, at least once the empire of Attila had broken up after 454. East of the Oder line poor soil would inhibit the growth of prosperous kingdoms; in real life the proto-Slav villages have yielded poor archaeological remains. It was no viable centre for resistance.
This would enable Romanization and Christianization of the more coherent Germanic peoples, probably the Franks, clearly from Gregory of Tours’ account already ruled by tribal kings (not only the Merovingian line) in the fifth and sixth centuries. Salian and Ripuarian (i.e. those on the Rhine river) Franks, in real life forcibly united by Clovis and his sons from about 480 to 550, already lived in territory within the Roman frontier at the mouth of the Rhine by about 400 and in real life expanded across Belgica in the next decades. If the Western Empire had lost control of that area after the invasion of 406 it could still have evolved into a separate kingdom under the vigorous Merovingian line, but if the Empire kept control of the Rhine area the Franks were the likeliest of the local peoples to cohere into a kingdom east of the river. As with allied German tribal states from the first century, the Empire would have an interest in establishing a friendly dynast who could control his people as its ally on the Rhine; the Empire could thus have backed the Merovingian dynasty as it established an allied kingdom in what became the eastern part of the real-life Frankish kingdom, Austrasia.
Rome could have been fighting and forcibly converting the disunited tribes of Saxons in the lower Elbe area in the eighth century as Charlemagne did in reality, with more troops so easier success despite the swamps and forests. It could then have moved on to annex other decentralised, badlyarmed tribes towards the Vistula, probably encouraged by a mixture of Church missionary zeal and a practical desire to stop independent tribesmen beyond Roman control aiding their resentful conquered relatives.
The Viking threat
In due course, a Roman clash with the Scandinavian Vikings (‘men of the viks/fjords’?) over control of the North Sea and raiding on Britain would have occurred. A united Romano-British kingdom in Britain that had been spared the real-life collapse of the fifth century, using Roman tactics and weaponry and cavalry to defeat raiders, would have put up a successful coordinated defence against all but isolated Viking raids and scared the latter off, particularly if they had a fleet and Roman naval aid. The first Viking attacks on the real-life small Anglo-Saxon kingdoms in the 780s and 790s appear to have been individual raids by opportunists, gathering in intensity and scope to a full-scale invasion by a large army under Viking kings in 865/6. In real life, the successes that the Vikings were having in moving up the great river-systems of France to pillage towns and monasteries encouraged the attacks on Britain, and the Frankish kingdom lacked a competent fleet or (after 840) a united politico-military leadership.
These problems would not have faced Roman Gaul, which had a Channel naval base at Boulogne (Gesoriacum) and could have called on the Imperial armies for defence. Co-operating Roman ‘duces’ would not have been as militarily weak as the Vikings’ Carolingian foes. The Vikings would have been more likely to attack an easier target, and the precedent of Saxon and Pictish raiding on Britain in the fourth century, if still remembered in Scandinavian sagas or retold by Saxon refugees, have suggested Britain as well as Ireland as a victim. Indeed, the absence of a Viking military presence in the Frankish kingdoms in the mid-late ninth century would have made it more likely that the full force of Viking expansion fell on Britain and Ireland in these decades. But some adventurous Scandinavians would have been content to take on Roman military careers, as men like Harald Hardradi of Norway did in Constantinople in real life.
A larger, united British kingdom would have had more resources to meet the challenge, including cavalry which the Anglo-Saxons lacked, and the Vikings may never have risked challenging such a well-prepared state en masse unless it was weak in its response to raids (as Ethelred II’s English kingdom was in the 990s). The Romans had more sophisticated weaponry in battle than the Saxon reliance on the shield-wall, and importantly had siegeweaponry that could tackle the Vikings if, as in the real-life invasion from 865/6 with its Viking encampments at York, Nottingham, Reading, Wareham, Exeter, and Chippenham, the latter tried to rely on a defended town to defy a local army. The Saxons could not wait outside a welldefended town indefinitely as long as their troops were only militiamen called up for a fixed term of service (the ‘fyrd’), a problem which Alfred of Wessex tackled after 878 by calling up his men in rotation.36 The British/ Romans would have had a professional field-army, and also have had the siege-engines to storm a Viking-held town and the ships to blockade a longship-supplied Viking base on a river like Nottingham (868) and Reading (870–1). Only in 868 did the forces of two Anglo-Saxon kingdoms fight the Viking Great Army together, and Northumbria (866–7), East Anglia (869), Wessex (870–1 and 875–8), and Mercia (868 and 875) were tackled separately by evidently superior Viking forces.
The provinces of post-Roman Britain should have been more coordinated. But a minority government, civil war, or resurgence of separatism in the Celtic kingdoms would have given the Vikings their chance and a major attack by a force of land-hungry Norwegians (or unconquered Danes) by circa 850 cannot be ruled out. Any serious British defeat and/or civil war in Britain could have led to a Roman reconquest, either directly or via an expedition to back up a pro-Roman candidate for the throne of the main kingdom in the South. The joint efforts of the British kingdom and a Roman expeditionary force should have outmatched any army that the Vikings could gather for a direct challenge, particularly if there had been naval attacks on the Vikings’ fleets as well. Denmark may already have been occupied by Rome, and if not it would have been an easy target for retaliation on land from Germany. Even a united Norwegian state such as that ruled by Harald Finehair (circa 920) or Olaf Tryggvason (990s) would have been vulnerable to a Roman North Sea fleet invading while the King was away fighting in Britain or Ireland.
The main Viking threat would have come from Norway, probably via the sea routes to the Hebrides and the Irish Sea to evade the Roman North Sea fleets. Rome would have been in a naval position to defeat any invasion by a massed fleet, though the manoeuvrable Viking longships would have had an advantage in evading their pursuers or in hit-and-run raids and Rome would have had to adapt its usual shipping to North Sea conditions. Rome may not have bothered to interfere with small Viking settlements in the isolated and agriculturally poor Orkneys and Hebrides. The likeliest area for large-scale Viking settlement would have been Ireland, which would have been likely to have a number of provincial kingdoms around 800 barring a major Roman military initiative to aid or conquer the High Kings. In real-life England in 865–70, the Viking Great Army picked off the Anglo-Saxon kingdoms one by one and even compelled one small kingdom (East Anglia) to lend them assistance to conquer another (Northumbria). The divided political nature of ninth century Francia was also invaluable to them. Ireland would thus have been their most tempting target. A prolonged bout of raiding or settlement, in real life, fortified bases on rivers accessible for their longships (Dublin, Waterford, Limerick), would have necessitated Roman intervention there if the local rulers proved inadequate defenders and the Church was complaining to the Pope about the sacking of monasteries.
Rome would probably have tried to impose pro-Roman chieftains in the nearer areas of Norway that their summer-time expeditions could reach from Britain or Denmark, South of Trondjheim. The serrated coastline and mountains would have impeded direct conquest and made the usual networks of roads and forts impractical, except in the Oslo plain where a Roman province could have been established to co-ordinate regular military intervention against such chieftains as continued to aid descents on Britain and Ireland. The Western Empire, like the East with their restless and potentially hostile Russian ally from 988, would have been keen to bind the Norse to them as allies. Thus the creation of the West’s own Varangian Guard of ferocious Viking mercenaries is a logical possibility, together with Viking officers emerging as Roman generals (as Germans did in the fourth and fifth centuries). By the eleventh century, talented scions of Viking kingly families such as Cnut the Dane and Harald Hardradi would have been natural recuits to the Roman army and possible senior generals, even commanding Roman fleets against their kinsmen. Given a weak ruling dynasty and factional strife over power in Rome, a senior general of Viking origin could have emerged as more likely to have set up a vassal Norwegian High King, in this case imposing Christianity on him too, than to have attempted full conquest.
If the smaller and militarily weak Irish states had been unable to cope with Viking plundering in the eighth and ninth centuries, their Church if not the proud chieftains could have sought aid from Rome as the leadership of Christianity, leading to the despatch of an expeditionary force. Roman technology and numbers should have prevailed over the invaders, but Rome is unlikely to have been able to afford the troops for direct control with most of the Western army still needed in Jutland/Norway/Eastern Germany. By this date the East had the naptha-based secret weapon, ‘Greek Fire’, to burn flammable wooden ships. It was first used against the Arabs in the siege of Constantinople in 674–8, and the West would have used this against Viking longships to devastating effect.