Roman Eternal Expansion: Dream, Folly – or Necessity?

The Roman Empire was one of the largest, longest lasting and most important states in human history.

It stretched from the Scottish border in the North to the Sahara in the south, from Spain in the West to Arabia in the East. It lasted for over a thousand years, two counting its Byzantine successor, and brought civilisation and unity to Europe.

- Advertisement -

Eventually like all empires it fell and from its ashes was born Medieval Europe. The reasons for its fall are many,  barbarian invasion, internal weakness and corruption, disease, climate change, over stretched borders, and lack of resources and development at the necessary crunch time.

The Gothic immigration that led to the disaster at Adrianople crippled them to an extent that they couldn’t hold off the ‘scourge of god’, Atilla, and by the time he was finally defeated Rome had been fatally weakened and slowly disintegrated over the next few decades until the deposition of the final emperor, Romulus Augustus, in 476.

Many have questioned this collapse and asked if it was truly inevitable. Obviously some things could have gone better, and different leaders may have made better decisions, but there were many long term effects that may have made it inevitable. Could it all have been simply down to the choices and views of the Romans though? Did they just need to continue the waves of expansion that stopped after the disastrous loss of Varus’ 3 legions in the Teutonburger Forest, and Augustus withdrawal from Germany? Some tried to repeat these expansionist moves, such as Julian, Septimus Severus, and more famously Trajan, but their conquests were short lived or given up by their successors. We must ask wether they should have tried to keep these territories, or if they were impossible to hold and just created to bring personal glory to an emperor.


Virgil said in the first century that Rome’s empire had no bounds. History seems to suggest the opposite, but is this the case? One of the simplest points is that a larger empire would have had a larger population and more cultivable land, agriculture being the main form of wealth, thus more tax revenues and more manpower, but to truly understand this concept we need to look at each of the borders in more detail, starting with Germania. This is really the centre of this study. Its relevance to the growth and later decline and fall of Rome are obvious. It was an area that had been considered for expansion by many of the most important figures of Rome, Caesar, Augustus, Domitian, Marcus Aurelius and later emperors like Julian the Apostate to name but a few.

- Advertisement -

The first attack on Germania superior (i.e. Germany east of the Rhine) was by Julius Caesar as part of his Gallic campaigns, however this was merely a punitive raid to prevent them assisting their cousins west of the Rhine. Augustus’ campaigns, led by Drusus the elder, succeeded in capturing all the territory up to the Elbe, but this only lasted until the famous defeat of Varus in the Teutonburger Wald in 9AD, and although Drusus son Germanicus succeeded in returning the stolen Roman eagles and devastating those tribes who had been involved, Tiberius decided to end the campaigns and return the border to the Rhine, ending any dream of a Roman controlled Germany; although this may merely have been due to jealousy and fear of Germanicus’ growing popularity.

Nearly two hundred years later Marcus Aurelius fought one of the longest and most difficult wars with the German tribes led by the Alemanni, Macromannic wars. As they were coming to an end with German defeat Marcus Aurelius decided to annex a great part of their territory, in particular the Bohemian plateau, thereby creating two new provinces. His untimely death in 180AD however, caused his son Commodus to come to power and he wanted a quick and easy end to the fighting, so merely concluded a swift peace treaty and gave up the plans for the creation of the new provinces.

While the withdrawal under Tiberius was quite logical, due to the lack of development and resources in Germany across the Rhine at that time, (in fact it cost them more to keep the land than they could gain in tax, as it couldn’t even provide enough grain to feed the soldiers stationed there) the later one could be seen as a terrible mistake.

The Bohemian plateau would have provided a reasonably wealthy area (Germania being more developed at that time) with far a clearer more defensible border. This would have been in the form of a series of narrow valleys, rather than a long river and forest frontier, which would therefore have provided greater safety from raiding and needed a smaller garrison, thereby saving the empire money and manpower. As the Rhine frontier became so a major weak point for the empire, suffering frequent raids, and later incursions, migrants and large scale invasions, strengthening this would obviously have been highly beneficial.

Recent studies by people such as Peter Heather have talked about the development and migrations of the ‘barbarian tribes’ of Germania. They have shown how they not only raided and fought with Rome, but were more deeply connected, and able to develop due to the impact of Rome. To sum up this large and complex area of study we can now see that the immediate frontier zone experienced rapid development due to its proximity to the Roman empire.

The opportunities for trade, not only with elite goods to the centre (mainly in the forms of furs and amber) but also in a more everyday sense providing food and goods to the soldiers guarding the border, meant these peoples became far wealthier and thus had the opportunity to create more developed societies of larger groups with more complex monarchical control. Moreover, access to goods and knowledge improved the farming techniques creating more heavily farmed areas, larger tradable surpluses and population growth.

This was a self perpetuating cycle that allowed them to keep on growing and forming larger groups, which competed with the other nearby groups, often leading to migration to the centre and conflict, to create bigger confederations then existed in the early empire, thus creating true threats to the Roman empire. Continued expansion could have kept ‘nipping this in the bud’, in other words if they had a policy of expansion whenever possible then they would have kept subduing the Germans and expanding into their improved territory, thus eliminating them before they became a problem, and ensuring the tribes at their borders were always small undeveloped and unorganised.

If the borderlands were therefore kept weak and underdeveloped then when the Huns arrived and tried to seize control of them the job would have been harder and less profitable, thus may never have happened, so the great empire of the Huns may never have reached the strength it did under Attila and become such a threat to Rome; and even if it did happen the populations unde his control would have been smaller and poorer, and therefore less well armed, again meaning a lesser threat to Rome.

Let us turn now to the case of Britannia. This was an area that had an unconquered northern frontier and dangerous western neighbour in the form of Ireland, or Hibernia as the Romans called it. Britannia was never fully pacified due to the changing political situations at court. Agricola was campaigning throughout Scotland during the 70s and 80, but was recalled by Domitian, supposedly because he was making the emperor’s own conquest in Germany look less in comparison. Later Septimus Severus again campaigned here and aimed to finish the conquest, but his death in York ended this for good. What would have been the result of the island’s complete conquest?

In the shorter term the pacification of the north would have meant that the enormous military structure that was Hadrian’s wall wouldn’t have needed to have been built, saving the empire a large expense. Additionally there wouldn’t have been the need for such a large garrison, as it should have followed the standard pattern of calming down and accepting Roman domination within a generation, as did most of the other conquests, especially those in northern Europe, thus saving more money and manpower.

We should also consider that the reason Britannia was abandoned was due to the constant pressure on Hadrian’s wall and the disinterest of a Roman state which, having more pressing (and nearer) concerns on the Rhine, wouldn’t or couldn’t send more troops. If this hadn’t been an issue Rome would have been able to hold onto this wealthy province.

It might also have meant that later expansionist emperors may have even moved on to a conquest of Ireland thus securing the western border permanently as beyond Ireland there is merely the Pacific ocean. There have been suggestions of a Roman presence in Ireland with the recent discovery of what appears to be a Roman fort in Carmanagh, near Dublin, and there’s a reference to a punitve mission in Agricola suggesting he crossed, and it was a common practice of Rome to interfere in the affairs of it’s neighbors, for example by appointing kings and providing financial and military assistance. So any emperor may have decided that an easy conquest like this would have brought them glory.

Reconstructed Roman tower : Wiki Commons

It is even possible that it was actually attempted, as, after all, military actions like this don’t often leave archaeological traces (In fact we only know of Caesar’s expeditions to Britain due to his writings). A final point to consider is that Britannia was beset by raids and piracy from Ireland and the Saxons, if the west was calm they could have focused their efforts on the east and so been better able to deal with this threat.

An interesting point to consider with this essay is Parthia. This, and more its successor Sassanid Persia, was the single greatest threat to Rome, being the only superpower they bordered. While the empire was generally able to defeat the earlier Parthian incarnation in most battles and had chipped away at its borders and surrounding client kingdoms they never really got very deep into their territory due to logistical reasons, and much of the territory they did take they were forced to give up, such as Babylon (whose Jewish population revolted prompting Jews in other parts of the empire to revolt)  and Trajan’s conquests. (Although Trajan can be said to have overextended himself, and only had the ability to take these lands due to Parthian internal fighting, which when resolved allowed them to return in force and kick the Romans out. For more information see Bennet’s Trajan:Optimus Princeps.) There are therefore two questions we have to ask, could Rome have expanded in this direction, and secondly would it have been worth it?

Parthia was an incredibly wealthy empire with trade connections going all the way to China  (Chinese ambassadors are known to have visited the Parthian court on several occasions) and was able to make huge sums as a middleman between east and west so it was always a tempting target for Rome. However its territory was incredibly large and most of it was arid desert and semi-desert thus any campaign was fraught with difficulties in supplying food and water for the troops. The only real chance of success here would have been to either continue to pick at is edges over time, or use an approach like Alexander the great and try to force a make or break pitched battle and eliminate the king, although unlike in Alexanders day the king had less power and a lot more was held in the council of elders and satraps; these could have been taken apart piece by piece, but it would have been a slow and difficult process. So coming back to the question of would it have been worth taking over Parthia, it can be seen that a full blown war of conquest would have been far too difficult, and that the path undertaken was probably correct, namely to pick around the edges and to mount occasional large scale raids. Sadly while this worked, indeed the capital, Ctesiphon, was sacked three times in the second century, this led to the collapse of the Parthian regime and its replacement by the far more aggressive, and therefore dangerous, Sassanid Empire.

The areas around Dacia, i.e. those outside the boundary of the Carpathian mountains pose some questions as to their value in greater Roman expansion. The area between the province and the Black Sea would have been tactically useful as it would have shortened the border significantly, and brought the majority of the coast under Roman control. While this area was indeed conquered by Trajan, it was given up by his successor Hadrian as it was too difficult to hold on to, its peoples being the nomadic Iazyges who weren’t settled in cities which could be easily overrun and garrisoned.

This situation was not to last forever though, and after these peoples had been conquered by the Goths in the third century, it would have actually been easier to take it from them and possibly prevent the need to retreat from the then surrounded province of Dacia. Any other areas outside of Dacia would not have really been valuable for conquest as they were again inhabited by nomadic peoples whose lifestyles made them hard to subdue, as mentioned above, and also as the Carpathian mountains provided such a strong and easily defensible border, it would have been unwise to give it up for the steppe land of the Hungarian Plain, unless Rome was expanding in a steady wave from the west and able to push all the way to the Dniester or indeed Dnieper rivers.

The kingdom of Crimea was a client state throughout most of the imperial period and though briefly annexed by Nero was given back its independence upon his death and stayed this way until late antiquity. It seems therefore that it was better to have this as a buffer state to protect the empire from the barbarian nomads that lived in the far northwest (as evidenced by it having Roman soldiers stationed there to assist their kings). Therefore, like with the Trans-Dacia regions, it would only have been worth taking over as part of a wider expansion.

Moving away from the frontiers there are a few other considerations when assessing this hypothesis. One of Rome’s strengths was its adaptability and acceptance of others, as it expanded it didn’t annihilate other cultures but rather absorb them and added their strengths to their own, for example Carthaginian ships, Spanish swords, Palmyran and Armenian cavalry, not to mention what they got from Greek culture. So as they expanded and took over more peoples, could they have developed and learned more? This is just speculation and we will never know for sure, but the idea of them reaching India or even China, throws up all kinds of possibilities.

One should also consider the role of the legions, which, while being considered one of the greatest military machines the world has ever known, had many weaknesses and often suffered from low morale, mutinies and lack of enrollment. This became more evident when Rome was no longer expanding as the men no longer had as much opportunity for gaining booty and slaves from defeated foes. An empire that continued to expand would not have had to suffer from this, as it would have given them more opportunity for wealth.

The final benefit of continuing expansion to consider is that it would have meant that the borders would have been pushed further out so when raiding occurred it would have been further and further from the centre. And as raids rarely got very deep in times when the empire was strong, more and more land would be spared the horrors of attack so would be able to develop and grow.

A stretch of Hadrian's Wall : Istock
A stretch of Hadrian’s Wall : Istock


However good an idea further expansion may have been we have to accept the realities of the ability to control such territories. The Roman empire was already massive and struggled to control its territories hence the need to split in two parts, which while weakening the west did allow the east to survive. Other problems that have been noted are divided loyalties; soldiers on distant borders had no contact or understanding of other parts of the empire and so were more likely to revolt and throw up their own emperors, and when one army did so the others often followed, as can be seen in the case of the famous year of the four emperors in 70A.D. after Nero’s assassination.

Another point to consider is that border defences and fortifications took time to build up and gain real strength. If it was constantly moving its borders they would have never gained much strength, inviting continual raiding. Although, conversely, a constantly expanding strong empire may have cowed many of their neighbours so reduced the possibility of this.

The key weakness though is that of the sheer size of the empire which meant that communication was frighteningly slow in an age before modern communication technology, even with the highly efficient postal service, the cursus publicus, it could still take weeks to get messages to the far flung parts of the empire, and soldiers even longer. Would a bigger empire have merely split earlier or into more separate parts, as with the effective yet extremely short lived Tetrachy? On the other hand the crisis of the third century was caused by these problems and the adaptations to this by the likes of Diocletian and Constantine gave the empire another two centuries of life, would it have simply adapted again, for example by increasing devolution and the size of the bureaucracy?


There would of course have been other avenues of expansion that I have not mentioned here. In the east we have Arabia, which being a desert would not have been likely to be absorbed at any point. In the south Meriotic Sudan and Ethiopia would have had similar logistical problems to Parthia, however, if the empire had remained strong and expansionist for long enough they may indeed have come under Roman domination. South of Roman Africa was the great Sahara desert, which provided a natural boundary to there southern expansion, and the only means there would have been sailing round the west of the continent, which, while possible, would have required a great distance before viable sites were discovered, although again with time and population increase this may have changed, and they may have continued in a means similar to the European empires of the 1500s, planting colonies at key points to control trade, e.g. the Dutch in South Africa.

To the north west lay Iceland, Greenland and eventually the Americas, but to reach these would have required superior sailing technology than existed in the empire, so would have not been likely targets without technological development, and afterwards of course, political will.

I personally believe that continuing expansion could have prevented the collapse of the Roman empire, as in effect it really collapsed in the west due to the Germanic influx picking it apart and taking its best land crippling it financially and leaving it unable to defend itself against the Huns and the groups that arose from their collapse, but a larger empire could have given up more territory and kept going. However, it was already too large having to split between east and west, so if it had been any larger it would probably have split into more parts, as in the 260s when it split between the Gallic empire, central empire and Palmyran centred empire. However, if the separate parts were not too many and managed to remain amicable and willing to coordinate in times of crisis, the empire could have gone on indefinitely. Indeed it may have developed more like China, dividing and reunifying under different dynasties but maintaining its cultural identity, if so the world would have developed in an altogether different way.

Written by Joe Medhurst

HeritageDaily : Archaeology News : Archaeology Press Releases



Julius Caesar, Bellum Gallicum.

Tacitus, Agricola.

Virgil, Aeneid.


Bennet,  Julian, Trajan: Optimus Princeps, Indiana University Press, 2001.

Breeze, David, The Frontiers Of Imperial Rome, Pen & Sword Military, Barnsley, 2011.

Casson,  L., Ships and Seamanship in the Ancient World (Princeton 1971) pp. 220 ff.

Goldsworthy, Adrian, How Rome Fell: Death of a Superpower, Yale University Press, 2010.

Heather, P., Goths and Romans 332-489, Clarendon Press§, Oxford, 1991.

Heather, P., ‘The Huns and the End of the Roman Empire in Western Europe’, English Historical Review cx (1995), pp. 4-41.

Heather, P., ‘The Late Roman Art of Client Management: Imperial Defence in the Fourth Century West’ in Walter Pohl, Ian Wood, and Helmut Reimitz, eds., The Transformation of Frontiers: From Late Antiquity to the Carolingians, Brill Publishers§, Leiden; Boston, 2001), pp. 15-68.

Heather, P., The Fall of the Roman Empire: a New History of Rome and the Barbarians§ Oxford University Press, 2006.
Heather, P., Empires and Barbarians: Migration, Development and the Birth of Europe, Macmillan§, London, 2009.

James, Simon, Rome & the Sword: How Warriors & Weapons Shaped Roman History,  Thames & Hudson, London, 2011.

Meyer-Zwiffelhoffer, Eckhard, Imperium Romanum. Die Geschichte der römischen Provinzen  (Imperium Romanum. The History of the Roman Provinces), Munchen: Beck 2009.

Shotter, David, Nero, Routledge, 2012.

Venning, Timothy, If Rome hadn’t fallen : what might have happened if the Western Empire had survived, Pen & Sword Military, Barnsley, 2011.

Warner, Richard, Yes, the Romans did invade Ireland, British Archaeology, no 14, May 1996.


- Advertisement -
Mark Milligan
Mark Milligan
Mark Milligan is multi-award-winning journalist and the Managing Editor at HeritageDaily. His background is in archaeology and computer science, having written over 7,500 articles across several online publications. Mark is a member of the Association of British Science Writers (ABSW), the World Federation of Science Journalists, and in 2023 was the recipient of the British Citizen Award for Education, the BCA Medal of Honour, and the UK Prime Minister's Points of Light Award.

Mobile Application


Related Articles

Study confirms palace of King Ghezo was site of voodoo blood rituals

A study, published in the journal Proteomics, presents new evidence to suggest that voodoo blood rituals were performed at the palace of King Ghezo.

Archaeologists search for home of infamous Tower of London prisoner

A team of archaeologists are searching for the home of Sir Arthur Haselrig, a leader of the Parliamentary opposition to Charles I, and whose attempted arrest sparked the English Civil War.

Tartessian plaque depicting warrior scenes found near Guareña

Archaeologists from the Institute of Archaeology of Mérida (IAM) and the CSIC have uncovered a slate plaque depicting warrior scenes at the Casas del Turuñuelo archaeological site.

Archaeologists find a necropolis of stillborn babies

Excavations by the National Institute for Preventive Archaeological Research (Inrap) have unearthed a necropolis for stillborn and young children in the historic centre of Auxerre, France.

Researchers find historic wreck of the USS “Hit ‘em HARDER”

The Naval History and Heritage Command (NHHC) has confirmed the discovery of the USS Harder (SS 257), an historic US submarine from WWII.

Archaeologists uncover Roman traces of Vibo Valentia

Archaeologists from the Superintendent of Archaeology Fine Arts and Landscape have made several major discoveries during excavations of Roman Vibo Valentia at the Urban Archaeological Park.

Archaeologists uncover crypts of the Primates of Poland

Archaeologists have uncovered two crypts in the collegiate church in Łowicz containing the Primates of Poland.

Giant prehistoric rock engravings could be territorial markers

Giant rock engravings along the Upper and Middle Orinoco River in South America could be territorial markers according to a new study.