Could The Roman Empire have conquered all of the British isles, had it chosen to try?
- Thread starter Parmenion
- Start date
A greater latin influence on the wider area as a whole, the potential for territorial butterflies once Rome inevitably starts to crumble, plenty of options such as that
Uh uh. Can't let you get away with that.
So the Romans get all the way to the tip of Scotland.... and then what? Going by the rest of England, they leave after a couple of generations. The Scotts go back to being Scotts. So what?
It could be possible but it would take such long time that single emperor hardly can do that taking how short times they usually lasted and them would have too other things to care. So that emperor's successor and probably yet successor's successor should continue that or else whole project is abandoned permanentally.
If they did, they are likely to stay merely out of prestige - one does not simply abandon places unless they really cannot hold them no matter what. The hardest part is cold and tribal Caledonia, Hibernia is definitely easier overall.
The most likely consequence alt-world has, there cannot be The Wall imagery in their Game of Thrones equivalent because the Legions would instead be housed in 3-4 Forts and deployed where tribal raids yet occur.
The most likely consequence alt-world has, there cannot be The Wall imagery in their Game of Thrones equivalent because the Legions would instead be housed in 3-4 Forts and deployed where tribal raids yet occur.
bguy
Donor
Would taking the remainder of Caledonia enable them to eventually station fewer troops in the British Isles? The Romans were able to substantially reduce the number of legions they kept stationed in Spain after Augustus completed the conquest of the region (eventually getting their garrison in the Spanish provinces down to a single legion.) If the same process played out in the British Isles that would eventually free up a couple of legions that the Romans could really use on the Rhine or Danube frontiers.
What Scotts? They dont exist yet, its all Picts up there.
Anyway if Agricola wasnt called back at the last second, then the Roman could have permanently established themselves in the lowlands of Caledonia. The plan was to starve the picts out by cutting them off from the lowlands breadbasket, through a series of forts sealing the Picts in the highlands called the Glenblocker Forts. With a legionary camp at Inchtuthil as the capstone of the whole defensive line.
Had the Romans had enough time to do so, they would have crippled the free Picts ability to suport their population or raid into Roman lands. A few decades down the line a renewed campaign for Caledonia could see the whole of Britain proper fall to Roman rule. Then with Britain settled, an attempt to take Hibernia to end the raids from there would finally make sense to try.
The Romans occupied the greater part of Britain for some 350 years. If the POD is that the invading Roman forces keep conquering instead of settling for the OTL borders, they'll likely conquer Scotland around AD 100 (maybe a decade or so later if we include stamping out the last vestiges of rebellion), leaving about three centuries (assuming they leave Britain at around the same time as IOTL) for Roman influence to reshape things.
One potentially huge butterfly: IOTL, the first Saxons were invited into Britain to help defend against Pictish and Irish raids. If the Picts and Irish have spent three hundred years under the same government as the rest of Britain, it's quite possible their raiding is butterflied away, and with it the whole Saxon settlement of England, with potentially huge (or not, depending on how big a believer you are in geographical determinism) effects on the islands' subsequent development.
Septimus Severus did conquer Scotland but then died and the Romans pulled back. But if they had conquered the entire British Isles the impact on the economy and military would be interesting. In later centuries without having to worry about raids from these regions more units could be concentrated on the Eastern coast. Stopping more raids would improve the economy and have a small but noticeable impact on the finances of the Empire as a whole. Having to govern a lot more land in the north we might see a more developed administration that could hold together if the Empire still falls apart. Or with greater forces at their disposal generals posted to Britain will launch more coup attempts.
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With the resources the Empire had at its disposal in the first and second centuries AD, yes, it could have pushed into the whole of Caledonia and even Hibernia if it had wanted to. But those resources would have had to come from somewhere else.
If they came from the frontier with Germania (which had been largely stabilised at that point but had quite a few legions assigned to it) then there's a good chance the Germanic tribes might have crossed the Rhine much earlier than they did OTL, which would not be good for the Empire in Gaul and therefore in Britannia too. At the very least, the Limes Germanicus wouldn't have been as far out as it was OTL.
If the resources came from somewhere else, then the Limes there would have been less well defended.
So although the answer, imo, is 'yes' it's actually 'yes, but at what cost?'
If they came from the frontier with Germania (which had been largely stabilised at that point but had quite a few legions assigned to it) then there's a good chance the Germanic tribes might have crossed the Rhine much earlier than they did OTL, which would not be good for the Empire in Gaul and therefore in Britannia too. At the very least, the Limes Germanicus wouldn't have been as far out as it was OTL.
If the resources came from somewhere else, then the Limes there would have been less well defended.
So although the answer, imo, is 'yes' it's actually 'yes, but at what cost?'
TBH I think the Empire of this period could have maintained two or three extra legions without much effort. Sure the rewards of conquering Britain might not be worth the cost, but I don't think the cost would be so great, or that the Empire's resources were stretched so thin, that it would require denuding other sectors of troops.
It kinda was that bad, even during just normal operations Britain maintained three legions at minimum. Which might not sound like a lot, but was a tenth the total legions Rome usually operated with. It was also barely enough to keep order in the province, and the only times the Romans ever really pushed the borders forward was when a fourth legion was lent to operations in the region. However this extra fourth legion rarely stayed for long, usually being borrowed from the Rhine forces and thus was needed elsewhere if nothing urgent was occurring in Britain itself. Agricola's great push for example was only feasible due to having four legions available to both hold the Britains down and push back the Picts.
Britain was a money pit for centuries, and with the worst threat it faced being raiders and not conquerors, it simply never made sense to keep four legions in the region for long enough to finish the conquest of the whole island. There simply always was a bigger issue somewhere else that would crop up and drag that extra legion away, and that was during the high periods of the principate. By the time of the Dominate, when Britain could finally afford to pay for the legions that defended it, it either had its men drained to defend the Rhine or usurpers would raise the legions of Britain to try (and mostly fail) to seize Imperial control which set back manpower in the region for a generation or more.
bguy
Donor
There's something to that, but it's not as though the Romans had no ability to expand the size of their army either. Rome had 25 legions at the death of Augustus, Caligula raised that total to 27, the number was increased to 29 by Nero and the various contenders in the Year of the Four Emperors, and I believe Domitian and Trajan each added an additional legion as well during their reigns. Moreover, since the 27 legions the Empire had for most of Nero's reign appear to have been adequate to maintain Roman territory (as seen by the Romans fighting the Parthians to a draw in the east while simultaneously crushing a major revolt in Brittania during Nero's reign), and there weren't any major new territorial acquisitions between the end of the Julio-Claudian dynasty and the reign of Trajan, that means the Empire theoretically had during the Flavian dynasty 2-3 more legions than it actually needed. (The Flavians having 29/30 legions during that time for borders that had previously been adequately defended by only 27 legions.) Those extra legions could have been used to conquer Caledonia without jeopardizing the Empire's security elsewhere.
Err, what Scots? Do you mean the Irish raiders ( at this point in time )? A Roman Britain that is the entire island will have a more uniform culture and identity. The Irish raids would be less successful and the entire colonisation of the far North might be avoided.
Uniform as in Roman towns and Celtic countryside? As for the Irish raids they would have a field day with Roman Scotland with their ships outmanaeuvring any land patrols.
Roman Scotland would ahve been a text book example of Imperial overreach, especially given that Roman southern Scotland was Imperial overreach on OTL.
Wouldn't the process of conquering and assimilating the entire British Isles lead to a integrated society that would only need limited protection due to it's geography?
I feel like in the long term that'd be cheaper than building Hadrian's Wall, Antonine's Wall, and keeping a permanently large garrison there that has to deal with raids from the North and West for multiple centuries.
I feel like in the long term that'd be cheaper than building Hadrian's Wall, Antonine's Wall, and keeping a permanently large garrison there that has to deal with raids from the North and West for multiple centuries.