Why did Rome, once a tiny town in the comparative backwater of Latinium, rise to dominate the entire Mediterranean basin? Empires rise and fall as a matter of course, but Rome’s unusual success, as compared to virtually every other state (both ancient and modern), does demand a special explanation. By Beloch’s calculations (1), by 400 BC, the total area controlled by the city of Rome amounted to roughly 900 square kilometers. In 117 AD, the year in which the Roman Empire reached its peak area under the emperor Trajan, it covered an area of 5,000,000 square kilometers (2), a figure more than five thousand times as large. And this land, unlike the areas conquered in the later expansions by the United States and the Russian Empire, was not largely uninhabited and sparsely populated. It was home to some of the largest cities in the ancient world, such as Carthage, Athens, Rhodes, Corinth, Alexandria, Massilia, Syracuse, and many others.
Unfortunately for us, the Romans themselves do not seem to have gone through much trouble to answer this question, at least in authors which we have access to. A favorite explanation, typical of ancient authors, was that the “gods had decreed it” or, as Livy says (3), “… the fates ordained the founding of this great city and the beginning of the world’s mightiest empire, second only to the power of the gods”, even decades before the legendary founding of the city by Romulus. A second explanation, favored by some ancient historians, was that the Romans always took the auspices and performed scarifies to the gods before engaging in battle. For instance, both Livy (4) and Plutarch (5) attribute the Roman failure to repulse the Gauls and the subsequent sack of the city in 387 BC to the failure of the Romans to carry out these rites. However, owing to the complete lack of reputable sources describing the religious activities of the Romans (or lack thereof) before they went into battle, we cannot regard this as a satisfactory explanation of the causes and effects of expansionism, however important it may be for students of Roman culture.
The only writer we have from the Republican period- that is, the period before the civil wars of 50-31 BC and the subsequent slowing of Roman expansionism under Augustus (6)- who addresses the question of causation in substantial detail is Polybius (7). According to him, the government of every nation passes through three stages, those of growing, peaking, and declining, and governments at their peak make better decisions than governments in either of the other two stages. Hence, a state like Carthage, which had been powerful long before the time of the Republic, lost the Second Punic War to Rome, as the latter was peaking while the former was declining (8). In a similar fashion, the Spartans failed at their goal of creating a world empire, while the Romans succeeded, because the system of Roman government was superior for such a purpose (9).
This explanation, although correct in broad outline, begs the question of what constitutes a “superior” government, or a “better” decision. One might initially suppose that the deciding factor is military, and that a better government is one that can conduct war more efficiently and capably than those of its neighbors. The Roman military, of course, was indeed formidable. It employed a complex system of organization and engineering that required Polybius more than twenty chapters of his sixth book to describe, even without going into detail on specific battles, or particular instances when this or that innovation proved to be of use. At the end of the second century BC, when Rome was firmly established as a world power, it had not lost a war in three hundred years (10); shortly afterwards, during Caesar’s Gallic campaigns, it is reputed to have crushed an enemy which outnumbered it by a margin of larger than 5:1 (11). (This is, of course, probably exaggerated, but given that Caesar learned of the details of the Gallic preparations for war from the same people who had originally made them, it is probably not completely fantastic.)
However, it is important to note that military prowess alone is not sufficient. For instance, the Spartans, whose military power was of such high repute that the legend of it survives to modern times, and who managed to become the dominant power in Greece by virtue of it, did not then go on to conquer the rest of the Mediterranean, and were indeed soon eclipsed by the Thebans, and later the Macedonians. The Macedonians themselves, who had shown such military brilliance under Alexander the Great, could not hold on to their empire either, and were defeated and later annexed by the Romans less than a hundred and sixty later, after the Battle of Pydna (12). And, of course, the Roman military machine was not invincible; most famously, Hannibal defeated one of the largest armies Rome could muster at the Battle of Cannae, even though his own army was only roughly half that size (13).
So, what were the key properties of Rome’s government that allowed it to create and maintain a global empire? The one obvious factor is Rome’s policy of assimilation- of exporting their own culture and citizens, and so forming a wider power base from which to draw support. Alexander the Great, despite subduing countless cities and millions of people, still fought his battles on the frontiers of India largely with Macedonian troops (14), troops whose homeland was only a hundred miles across and more than a thousand miles away. Once these troops left, local rulers had no reason to stay loyal to Macedon, and indeed promptly formed their own independent kingdoms.
Rome, on the other hand, had a policy of selling many of the people of conquered cities into slavery- a logistical feat impossible for a roving army such as Alexander’s- and then settling the land with colonies formed from their own citizens. For instance, during the four-year period from 297-293 BC alone, Roman armies enslaved roughly 60,000 people (largely Samnites), a figure which composed a substantial fraction of the entire Roman population at the time (15). Meanwhile, Rome had founded more than twenty colonies in central Italy, many adjoining Samnite territory (16). This large base of land and support in Italy gave the Romans the resources to defeat Pyrrhus’s Greek army, and later Hannibal’s Carthaginian army, through persistence and attrition (17), even though the casualty ratio in both battles was lopsided in the enemy’s favor (13, 18).
However, there is also a second, more subtle factor, this one generated by the structure of Roman society itself. By far the largest way a Roman aristocrat could gain political power- that is, apart from the accident of birth, which the individual has no control over- was through military prowess and the glory of victory in battle. Indeed, the “real kernel of the office” of consul, the highest position in the Roman government, was the position of a general and military commander, and it was quite unusual for a consul to not go to war during any given year during the time of the Republic (19). As just one example of many, the famous M. Licinius Crassus, although already one of the most powerful men in Rome, was willing to go to such lengths to attain a military triumph that he was eventually killed during his attempt (20). The common soldiers also greatly desired glory, and would go through great hardship to risk it (21, 22), although of course the bulk of the glory was reserved for officers and aristocrats (23).
In addition to this, there were numerous economic motivations for war. Now, by “economic motivations”, let us not suppose that a Roman general of 200 BC went to war primarily to enrich the Roman state, any more than an English businessman of 1900 AD worked primarily toward the goal of enriching the British crown through the taxes he paid. No; by “economic motivations”, we must mean that participants in the war stood to gain personally (or through allies), either in the form of land (the chief source of wealth in the ancient world), or through booty, such as gold and silver. For instance, we see that, during the middle of the second century BC, while there were numerous volunteers for a potentially profitable campaign against Carthage, the citizenry as a whole had begun to dislike the military draft for wars that were generally unlucrative, such as numerous campaigns in Spain (24).
As a result of both of these motivations, we should readily infer that the Roman population, including both the upper and lower classes, was generally in favor of war, and opposed to peace. In fact, the inference is not even necessary, as the fact of the matter is quite well attested in our original sources. Livy says that the doors to the temple of Janus were closed (signifying peace) only twice before Augustus, over a span of some six hundred and fifty years (25), and Polybius testifies to the fact that the Romans relied heavily on violence in all their endeavors (26). Although the Romans of the imperial period often revered peace, and claimed that Rome had already attained world domination and therefore had no need to expand further, the Romans of the Republican period usually did not (27).
Hence, until the policies of the Roman Republic changed (as they did under Augustus), we may say that there were only two possible stable outcomes: Roman domination of the known world, or the conquest of Rome by an outside power. Any state intermediate between those two would, sooner or later (usually sooner) lead to another war, and another roll of the dice, because of the thirst of the Roman leadership and people for the rewards that war would bring.
As a case study of this pattern, let us examine the struggle between Rome and Carthage for control of the Mediterranean basin, during the third century BC. First, let us dispense of the notion, plausible on the surface, that peace was the usual condition and war was the exception. The first peace treaty between Rome and Carthage is recorded by Polybius to have taken place in the year after the founding of the Republic, or circa 510 BC (28), and the city was destroyed by Scipio Aemilianus in the year 146 BC (29), for a total span of roughly 360 years of coexistence. Out of this time period, the three Punic Wars take up 43 years, or less than 12% of the total, so it might at least sound plausible to claim that the Romans did not usually desire war.
However, let us examine this claim in more detail. During the entire period from 510 BC, down to when Rome finished the conquest of southern Italy in 272 BC with the capture of Tarentum (30), we can safely say that full-scale war between Rome and Carthage was impractical, owing to the limitations of ancient armies, combined with the fact that the two states essentially did not share a border. Additionally, during the 230s BC and the first half of the 2nd century BC, Carthage was making large annual indemnity payments to Rome (31, 32), and so Rome had a large, direct financial incentive to not engage in a war which would terminate them. Subtracting these periods, there was a total of 66 years during which war between Carthage and Rome was a viable proposition, and the 43 years of actual war are then seen to be almost two-thirds of the total, by far the dominant portion.
Now, let us examine the three Punic Wars in turn. At the beginning of the first, Rome seems to have been genuinely hesitant to intervene (33), largely owing to their repulsion from the blatant immorality and un-Romanness of the Mamertine sack of Messana. However, the Romans knew, in a sense, that war between the two great powers would probably happen eventually, as they feared the domination of the lands around Italy by a single, strong foreign power, which would then be in a position to attack them and win (34).
After this point, however, Rome effectively committed itself to, not just a limited war against Carthage or Hieron of Syracuse, but to a decisive victory or defeat. The First Punic War proved to be enormously profitable, with the enslavement of tens of thousands of people and the presumable capture of a great deal of booty, which was advertised to the citizens as a reason for them to support the war (35). Hence, even after Hamilcar Barca was defeated at the battle of Agrigentum, the Senate and the people of Rome voted to continue pushing further and further until the Carthaginian forces were decisively driven from the island, even though this took over twenty years, and involved much risk and sacrifice on Rome’s part. This continued even after the end of the war, with the forced Roman annexation of Corsica and Sardinia.
The Second Punic War began in much the same manner as the first: the Romans, worried about Carthaginian expansion into northern Spain, decided to take the offensive to check Hannibal’s army, and declared war against the Carthaginians in spite of there being no sound legal basis for it (36). It is important to note that, although Hannibal decided to take the initiative and move into Italy (most probably a wise move on his part), the declaration of war was not his; he was reacting to the prospect of a Roman invasion force descending on Spain and Africa (36).
On this roll of the dice, however, their plans backfired- Roman leaders who had gotten themselves into a war through visions of glory, and a Roman conquest of Spain (37), soon found themselves facing an army in Italy which, apparently, could not be beaten back by Rome’s legions. Although Hannibal’s plan was not total conquest, he himself foresaw that, should the war end in a Carthaginian victory, the Romans might seek a third war (38), which would then quite probably lead to their destruction, much as it led to Carthage’s destruction by Scipio Aemilianus. It is, therefore, quite likely that only the determination of the Senate and people, as illustrated by Polybius (39), made the final outcome of the Roman state world conquest rather than total defeat.
As for the Third Punic War, it should be obvious to all that Rome was aggressive even by Roman standards, as illustrated by Cato’s famous statement that “Carthage must be destroyed”, which he placed at the end of every speech regardless of subject matter (40). Polybius tells us that the Romans had already decided to go to war long before the actual declaration (41), and we may safely presume in this case that they were merely waiting for the indemnity to expire before finding a pretext for the declaration, owing to the temporal proximity of the two events. The allies of Scipio Aemilianus, who stood to benefit the most, quite plausibly played a significant role in this, although our confidence in this is limited, owing to our lack of sources about the Senate during this time period.
Lastly, we should at least mention Carthaginian actions. Although the Romans took the offensive initially during all three wars, it is not true- far from it- that Carthage was a peaceful state and Rome’s wars were purely aggressive. Carthage was an expansionist power, it had sought to expand militarily in Spain just as the Romans had (42), and perhaps (though it is hard to tell for certain, owing to the lack of primary sources) it also had dreams of worldwide empire. The primary difference between the two, it seems quite plausible, was that Rome relied more on direct military might, while Carthage relied more on economic power, such as its mercenary armies. Hence, there is room for both a pro-Roman and a pro-Carthaginian interpretation, the latter being that Rome was overly aggressive and militarily ruthless, the former being that the Romans were more competent at grand strategy, and just had the courage to do what it took to win.
In conclusion, Rome’s policy of assimilation provided the means, and its glorification of military service and victory the motive, for its eventual world empire. The secret of Rome’s success lay largely in the fact that, to quote Polybius (26), “… the Romans rely upon force in all their undertakings, and consider that having set themselves a task they are bound to carry it through, and similarly that nothing is impossible once they have decided to attempt it.”
(1) Harris p. 60.
(3) Livy I.4.
(4) Livy V.52.
(5) Plutarch, Life of Camillus, 18.
(6) Woolf p. 180.
(7) Harris p. 107.
(8) Polybius VI.51.
(9) Polybius VI.50.
(10) Hildinger p. 34.
(11) Caesar VII.75.
(12) Bringmann p. 99.
(13) Livy XXII.46.
(14) Plutarch, Life of Alexander, 62.
(15) Harris p. 59.
(16) Bringmann p. 28.
(17) Bringmann p. 34.
(18) Plutarch, Life of Pyrrhus, 21.
(19) Harris p. 15.
(20) Plutarch, Life of Crassus, 14.
(21) Sallust, Catilinian War, 7.
(22) Polybius VI.54.
(23) Harris p. 30.
(24) Harris p. 50.
(25) Livy I.19.
(26) Polybius I.37.
(27) Woolf p. 184.
(28) Polybius III.32.
(29) Bringmann p. 131.
(30) Livy XV (epitome).
(31) Polybius I.63.
(32) Livy XXX.37.
(33) Bringmann p. 65.
(34) Polybius I.10.
(35) Harris p. 63.
(36) Bringmann p. 76.
(37) Harris p. 205.
(38) Bringmann p. 81.
(39) Polybius VI.58.
(40) Plutarch, Life of Cato, 27.
(41) Polybius XXXVI.2.
(42) Bringmann p. 74.
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