The Western Roman Empire in Exile

[procrastinating2much]

So, what if Britannia had been developed more during its time as a province? Maybe if, at its peak, Rome had managed to make temporary peace with tribes at least in the south to build up a solid Latin speaking population and large cities. During the gradual collapse, the Romans hold onto the island instead of retreating, seeing it an important economic province instead of a wild frontier. When Italy faced invasion during the Gothic Wars, what if Stilicho, Honorius' guardian and competent general, had made preparations to evacuate the entire Roman government to London before his assassination? How would this Roman state survive with only Britannia left? If at least the south was more Romanised, could a Roman Empire successor state similar to Byzantium thrive, remaining isolated from European politics?

I'm trying to write a timeline where this is the case, and Rome survives in some form until at least the mid 6th century (because realistically, they still have all the odds stacked against them). I figured there would probably be some form of division between tribes of Britain supporting the Romans, such as the Catullauvani in Superior, and ones that aim to bring it down, such as the Brigantes. So I imagined a sort of civil war in 550AD. I have thought and researched a lot into it but I am probably missing stuff!

So what I've tried to show here is the division of Britons in 550AD, under the Emperor Honorius III (I got creative with the names as you can see). I also tried to think a bit about areas of support for the Emperor so I can begin to imagine where areas of conflict would occur, and whereabouts it would begin to collapse.

(Anyways, small notes: the Saxons mostly came to Britain in the power vacuum that followed the collapse of the Roman Empire, so without its fall in Britain at least, this probably wouldn't have occurred.)

This is my first post here and I'm not feeling too bad about how it's turned out, and I want to develop it a wee bit! Let me know if I messed anything up haha

 

[procrastinating2much]

Instead of Stilicho founding this successor state, what if the POD was much later, in 407. Constantine III fails to invade Gaul due to poor weather conditions in the English Channel and is forced to stay in Britannia. He would have access to an army of 120 thousand including families. This is enough to control the province if managed correctly, assuming relatively peaceful relationships with tribes. However, his main problems would be the declining economy (although this could be revived with a continuation of coin minting) and troop loyalty. Before his nomination, the army had nominated two other leaders and killed them for failing to act to prevent the barbarian crossing into Gaul in 406/7. If Constantine managed to provide a sense of security to the Roman army and their families in Britain, maybe by making treaties with tribes in the north and refortifying Hadrian’s Wall, would he still face likely assassination from them if he did not invade the mainland western empire?

 

[procrastinating2much]

HISTORY - 407AD
Point of Divergence and Constantine's rule of Britannia

The year is 407AD. Britannia, the northernmost province of the divided Empire of Rome, faces collapse.

In absence of the garrison stationed in the North and West of the island have been withdrawn to face Alaric, barbarian tribes from Hibernia, Caledonia and the North remain uncontested. In the South, Saxons raid the grand villas of the Roman elite, once enriched by the trade from the islands great metropolis’s: Londinium [London], Camuledunum [Colchester] and Eboracum [York]. Roman money minting has halted in its entirety.

In Gaul, large tribes of Vandals, Burgundians, Alans, and Sueves crossed the Rhenus [Rhine], overwhelming Roman defenses and threatening the collapse of the Empire. The provinces of Britannia, facing separation from the mainland, revolt. Desperate for a sense of security, the Roman armies stationed in Prima elected a common soldier of significant ability for leader, named after the famed fourth-century emperor, Constantine.

Constantine the Great had arisen by military coup originating in Britain in 306AD. To follow his footsteps, Constantine III would cross to the continent with the remaining army of fewer than 125,000 men and their families, including dependents.

[POD] The crossing was a disaster.

The Roman forces met at Portus Dubrae [Dover]. Only half of the Roman army would follow Constantine out of port. The ships didn’t make it halfway before a terrible storm diverted their course. The leader found himself washed ashore at a farm near Anderida [near Folkestone]. The 30,000-remaining led by Iustinianus and Nebiogastes, appointed magistri militum by the would-be usurper, would begin to enact strict discipline for his army while Constantine lay recovering. His recovery would be slow, and his wake would be greeted with betrayal. Nebiogastes had seized control of a small army after murdering his wife and his son, Constans (whom Constantine had placed in charge of Britannia) and departed west with 15,000 men who had declared him emperor.

Constantine led his remaining army west, following the traitor to Venta Belgarum [Winchester]. The Battle would be a short and bloody victory for Constantine, who had surrounded Nebiogastes with the promise that any traitorous soldier would be allowed to re-join his ranks to be spared if they chose to fight for him. Constantine established himself in Londinium, a city of 60,000, with nowhere near enough men to pose a threat to the boy Honorius on the throne in Italia, but safe in the knowledge that, for now, he would not be pursued by legion while the emperor faced annihilation by Alaric’s Visigoths.

Constantine would rebuild and reorganize his army until early 408, controlling land in the south of the Empires former frontier. In the North East, a Roman army matching the size of that loyal to him under the rule of a former aristocrat, Julius. Constantine knew he had to act to unite the Roman armies and usurp Honorious. Before his nomination, he and his fellow troops had killed their leaders for failing to act against the barbarian crossing of the Rhenus into the Empire.

Iustinianus knew that Julius would retreat to the natural marshlands in the north once the base of his rebellion, Camulodunon, fell to Constantine. Combatting this, he led a division of 2,000 men to secure the marshes. Half of those would march north and join a smaller division of soldiers in Maxima Caesariensis [Yorkshire] and prevent a revolt from the Brigantes.

Constantine led an army towards Camulodunon and took the city without much resistance. Julius retreated north and met Iustinianus’ division and were slaughtered at the Battle of Camboricum. Constantine had established control over the south of Britannia.

Yet the would-be usurper would not yet cross the Oceanus Britannicus [English Channel]. News soon reaches the leader in Londinium, Saxons have seized the opportunity arisen by the chaos of Britannia, invading the undefended shores of Metaris Aest [the Wash] and pushing south. The Roman garrison at Durobrivae [Castor] is defeated, leaving few towns in defense of Londinium.

As the last act to retain power, in 411 Constantine calls for magistrates to surrender wealth to him or have it lost to an overwhelming Saxon force. With this, combined with conscription for those within the city, creates enough resistance to drive Saxons north. Constantine declares the construction of forts along the undefended shores. With lack of men to invade Gaul, this act signals the leader's decision to consolidate power on the island, to retain the Roman culture of the territory still in his possession.

By 412, the Roman Empire had lost Hispania and much of Gaul. Honorius remained on the throne. Constantine is in control of 10,000 British and Roman soldiers. While chaos in the northern regions of Britannia remains, for the time being, the relative stability of the south creates no appetite for a return to the chaotic continent.