Cannae Part I

The winds of change echoed along the Tiber as the year 216 began, and though a skeptic might have heard the winds howling disaster, most Romans seemed confident they were blowing toward a quick and decisive victory.

The strategy seemed sound; pressure would be applied in all the appropriate directions. Marcellus, the reliable and hyperbelligerent spolia opima winner, was sent to keep an eye on Sicily, the fleet there having been augmented for a potential invasion of Africa. More on target, in late 217, Publius Scipio, now recovered from his wound, had joined his brother Cnaeus and his two legions in Spain with eight thousand fresh troops and a small fleet. Both Scipios had been given the proconsular imperium to tear up Barca land and rob Hannibal of his base. Nor was Hannibal’s Gallic connection overlooked. Twice-consul L. Postumius Albinus was given two legions and dispatched north to break the rebellion in Cisalpine Gaul and seal off any further support from that quarter. But the central objective, the overwhelming priority, was to directly confront Hannibal and crush him beneath the weight of Rome’s key advantage, military manpower. Everything points to a corporate decision to stage a great battle and obliterate the invader once and for all. Fabius was out, the bludgeon was in.

Viewed from the comfortable perspective of subsequent events, the reasoning that led to Cannae is easy to dismiss. But it was far from implausible. Arguably, there was a fundamental Hannibal problem: if you didn’t beat him, you couldn’t get rid of him. On the other hand, if the Punic force were to lose even one significant battle, it was too far from any secure base to survive. Just one Roman triumph, a single day’s victorious fighting, would put an end to the invasion. The string of previous defeats could be convincingly attributed to impulsive commanders, impiety, bad weather, bad luck, bad timing … The excuses were endless. Meanwhile, Romans still had good reason to believe in their military system—after all, its fundamentals would provide security for nearly another half millennium. They had merely to supersize it and leave nothing to chance.

Of course they were wrong, and Fabius Maximus had been right. Lacking a secure base, Hannibal probably could have been attrited out of existence. But the victory at Cannae would allow him to sink his claws deep into Italian soil, and then he would prove far harder to uproot. So the battle proved to be much more than a human tragedy and a tactical debacle; it was the strategic basis of fifteen more years of Hannibal, what must have seemed at times like perpetual Hannibal. About the only things the Romans could salvage from Cannae were Scipio Africanus and perhaps ten thousand disgraced survivors, and one day they would avenge themselves and Rome by drawing the Carthaginian away and then defeating him nearly as badly as he had defeated them. But that day was still far in the future.


Deciphering any political environment is difficult, more so an environment twenty-two hundred years old and littered with deceptive contradictions, patronage relationships, and family alliances. Although modern historical scholarship has clarified the climate of opinion and motivation to some degree, we will never know exactly what Romans were thinking in 216. Therefore, while it is possible to say that as the year began, attitudes had hardened and grown more overtly aggressive, certain issues remain veiled in obscurity.

For example, Livy (22.33) tells us that a Carthaginian spy, who had gone unnoticed for two years, was caught right around this time. His hands were cut off, and then he was let go. In the same breath Livy adds that twenty-five slaves were crucified for forming a conspiracy in the campus Martius, the field where Roman troops customarily drilled. The two events seem related. Why else would they be mentioned together? Also, from this point Hannibal’s intelligence advantage begins to diminish, or at least it appears to, on the basis of available narratives. Was this spy the Punic mole, and were these slaves his spy ring? It can be inferred as such, but not with certainty. It may be that the Romans avoided saying too much about what could have been considered an embarrassment and a vulnerability.

Other deceptions are more apparent. Both Livy and Plutarch would have us believe that the consular elections of that year, which determined the commanders at Cannae, were basically contests between the impulsive “people,” whose choice was the lowborn knave and demagogue C. Terentius Varro, and the prudent patriciate, who managed to secure the elevation of the wise and experienced Lucius Aemilius Paullus as a brake on his hotheaded and foolish colleague. The historians even stage a tête-à-tête during which Fabius and Paullus agree that the former’s strategy of avoiding battle is the best approach and that the impulsiveness of Varro is virtually as dangerous to Rome as Hannibal. Livy even insinuates that on the day of the battle, Varro issued his orders to fight without bothering to inform Paullus. Polybius, while less hyperbolic in his denunciation of Varro, is nevertheless plainly sympathetic to Paullus and largely absolves him from blame. But all of this becomes more difficult to swallow in light of the fact that after Cannae the apparently incompetent Varro was given a number of other important commissions and even military commands—although this also may have been a means of shifting the blame. Meanwhile, Polybius’s exculpatory portrayal of Paullus fades somewhat when it is realized that Paullus was the grandfather of the historian’s patron, Scipio Aemilianus.

Modern historians have come to understand that a more likely explanation is that Varro, the first member of his family to rise to the consulship, and largely without illustrious descendants, was tagged by later generations as Cannae’s designated scapegoat, while Paullus’s reputation was rescued by the later propagandizing of his powerful family.6 Actually, Varro may have served under Paullus during his first consulship three years before, when they’d been campaigning in Illyria, and both were probably now on the same side of the debate over how to fight Hannibal.

This amalgam of confrontationists was likely built around the powerful families of Aemilii and Cornelii, particularly the Scipionic branch, and included Minucius and Metilius, the tribune who’d worked to elevate Minucius to equality with Fabius Maximus. Probably they were opposed by the Fabii and the older, more conservative members of the senate, who could be assumed to have stood on the side of patience and the gradual attrition of the invader. Yet the policy of patience was plainly in eclipse, perhaps even among some of its adherents. After all, they were every one of them Romans, and the Roman default position was to fight. A measure of this enthusiasm was that as many as a third of the senate joined the army at Cannae, and most of the other senate members had close relatives among the ranks. This showdown with Hannibal was intended to be the magna mater of all battles, and an analysis of those selected for magistracies in 216, especially as military tribunes, shows them to be considerably more experienced in military matters than was usually the case. Plainly much of the leadership was ready to stake their future and the future of their respective gene pools on this gigantic roll of the dice.

So were the rest of Rome and Rome’s allies. The contemplated instrument of destruction was to be an army roughly twice the size of any previously assembled by the Romans to operate as a unit. Varro and Paullus would each command double armies of four legions plus equivalent allied units, but the whole mass was expected to fight together—eight legions and eight alae, in effect a quadruple consular army. Given that a Roman army operated best as a maneuver unit when it was composed of two legions and two alae, there was reason to suspect that this monster might prove inherently unwieldy—a lumbering Frankenstein of a force at best, and at worst a paralytic, a quadriplegic consular army. And this raises the question of who actually would be in charge overall. Meanwhile, to compound the effect, each of the legions, and presumably the alae, was increased from forty-two hundred to fully five thousand, which added up to a grand total of eighty thousand infantry. As we shall see, quantity had a quality all its own … but not the one the Romans expected.

The sole area where the force seems somewhat shorthanded was cavalry—six thousand, two thirds of it allied, when the normal legionary and alae component might have been expected to yield almost ten thousand. Apparently recent losses, especially those of Centenius, had taken their toll, and this too would prove telling at Cannae.

More specifically, the army that would confront Hannibal had two basic components. The first was the force left to keep an eye on him at Gerunium, an experienced element with a history of heart-stopping ups and downs—mostly the latter. Its core was built around the two legions that Publius Scipio had managed to salvage from the defeat at Trebia, soldiers who earlier had been repeatedly ambushed by Gauls. The legions had later been taken over by Geminus, then transferred to Fabius Maximus to chase and lose Hannibal, and then they’d nearly been destroyed under Minucius. To make up for casualties and other attrition, they were bound to have been reinforced on multiple occasions, but at least the veterans had served together and under the same officers for a period of years.

The second element was essentially virginal, the Roman portion consisting of four new legions all recruited around the beginning of the year. While these troops as individuals appear to have received the rudiments of military training as part of their upbringing, the process of integrating them into maniples and teaching them to fight as units not only took time—presumably the spring and early summer—but would have resulted in only a thin behavioral veneer of mutual trust and confidence, which, without the experience of actually fighting together, could be ripped away fairly easily in an emergency to reveal a substrate of panic and helplessness. Next to nothing is known about the allied components, but if this was a newly recruited force, it’s hard to imagine they were any more tested than the Romans, nor would they have been used to their officers, who were also Romans.

It is not clear when the two forces joined together. Polybius (3.106.3) talks about sending new recruits forward for experience skirmishing, but these recruits appear to be reinforcements for the legions already at Gerunium. Although Livy (22.40.5) maintains that the new legions arrived before Hannibal left winter camp and headed toward Cannae, modern opinion favors a delayed linkup, as late as less than a week before the battle. Given this, it’s hard to imagine that the Romans’ juggernaut was in any meaningful way integrated; rather, it remained two separate armies that on the day of battle would be cut up and welded together for its moment of truth, tactically a dubious proposition.

Yet it could be argued, and probably was at the time, that the Roman military system made their troop formations inherently interchangeable, and therefore more easily mixed and matched. No doubt the injection of experienced leadership was counted upon as a lubricant. And there was the intangible of morale. The allied forces in particular were furious over Hannibal’s rampage across the Italian countryside and were vengefully eager for combat. Meanwhile, the Roman troops seem to have been embarrassed, not daunted, by previous defeats and were now grimly determined to prevail.

To seal the deal, the establishment did something unprecedented. Livy (2.38.2–5) tells us that once the allied levies arrived, the consuls had the military tribunes formally administer an oath to all the infantry and cavalry that they would depart from their ranks only to secure a weapon, kill an adversary, or save a comrade. Previously, the historian notes, this had been a voluntary pledge among the soldiers themselves; now flight in the face of the enemy was against the law. To some societies and some armies this might have seemed a mere formality, but the Romans were literalists and legalists. And as we shall see, it was this oath that would determine the fate and futures of those who might have thought themselves otherwise lucky to escape the death trap at Cannae.

As a fighting force, the fated quadruple consular army was large and full of Romans, both good things. But it was also full of vulnerabilities. It had a substantial number of light troops, perhaps as many as twenty thousand, but they were of suspect quality. If not the “armed servants” one source calls them, they were clearly not as effective as their Carthaginian equivalents. These soldiers had been scattered like chaff at Ticinus and Trebia … though they did seem to stiffen somewhat under Fabius and Minucius. Still, it is probably telling that Rome’s staunch ally, old King Hiero of Syracuse, looking for ways to help, thought it wise to donate one thousand light troops of his own, some of them archers (apparently the only archers at Cannae).

The cavalry was probably even weaker; it had already suffered savage losses, and the skills involved are not easily replicated on short notice. The ranks were probably swelled a bit by members of the senate, who were by definition equestrians, yet many would have been old and past their military prime. Besides, the majority of cavalry were allies, and Hannibal’s well-advertised leniency toward them could be expected to have an impact on their fighting spirit in a pinch, especially among forces with the greatest ability to get off the battlefield in an emergency.

The obvious strength of the Cannae army was its heavy infantry. Even if it could not be screened effectively by light troops and its flanks protected by cavalry, it was big enough to be relatively immune from harassment, provided it could maneuver and win decisively with some degree of dispatch. Yet this was also a force subject to emotional volatility—its better half, the experienced element, had been defeated more than once by Hannibal, and the other part was a mass of neophytes, with all that that implied. Temperamentally, it was an army likely to overreact—prone both to excessive enthusiasm and passive despair. Judging by his plan and its results, this was exactly what its Barcid nemesis anticipated.


It is not certain when Hannibal left Gerunium and headed south, but he likely would have waited until the early summer, when the crops were ripening and his troops could forage. Livy concocts a tale of an attempted ambush and then a night escape in the face of the already united Roman army, but Polybius’s version that Hannibal marched out past the guarding force of Geminus and Regulus, who were under orders not to engage until Varro and Paullus arrived with the rest of the army, is simpler and more plausible.18 The historians agree on one point: the Punic force was hungry. Whether on the basis of good luck or good intelligence, Hannibal gravitated to Cannae, around sixty miles south of Gerunium, nearly to the Adriatic coast. Here he captured a grain storage and supply dump in the ruined citadel on the heights of the otherwise abandoned town. His food problem solved, at least temporarily, he made no further effort to move, and this was telling.

Cannae sat at the bottom edge of an immense treeless plain, the largest south of the Po.19 It was ideal for cavalry operations and large-scale maneuvers, exactly the terrain for magnifying Punic military advantages. By this time Hannibal probably understood that the Romans were intent on a showdown and were putting together a monster of an army for the occasion. So far, his efforts to chip away at the Italian alliance had come to nothing. He needed a really spectacular victory to generate the kind of political impact to begin breaking off Rome’s affiliates. This was the perfect time and place to inflict it. Staying here was tantamount to accepting the challenge. He had only to await his opponent’s arrival.

But, being Hannibal, he probably kept himself busy preparing the reception. If we accept Polybius’s version of the events leading up to the battle, the Punic army may have been alone at Cannae for several weeks. This is a dangerously long time to give any commander to prepare a battlefield, much less a commander with Hannibal’s fertile military imagination. By this time he was likely on a first name basis with every rise and depression, every twist in the River Aufidus, every potential campsite, every approach and escape route, every possible advantage he could squeeze out of the surroundings and then blend with a battle plan that seems to have been derived from his cumulative observations of Roman fighting tendencies and the capabilities of his own troops. As always, much remained to be determined by chance and the circumstances of the actual engagement, but it’s a safe bet that during this respite Hannibal’s mind seldom wandered from the upcoming test.

His plan when it was finally hatched implied a great deal of faith in his army. This faith was not misplaced. The gang of desperadoes that had stumbled off the Alps not much more than a year and a half earlier had been but a scrawny prototype of the force that now awaited the Romans at Cannae. Freeze-dried no more, the men and horses had regained their health, had eaten their fill, and were rested. We know that key elements had been systematically rearmed with the best of the captured equipment, and it is likely that many others had picked up bits and pieces of what had once been Roman weaponry.

Another change had to do with the Gauls. By this time they were much more reliably integrated into the fighting force. They still fought together, to take advantage of their peculiar tactical characteristics, but at Cannae small units of Gauls were interspersed with Spaniards, indicating that their tribal allegiances had been effectively superseded by the command system that controlled the rest of the army. Very likely the process that had begun for the Gauls on the slog through the Arno marshes was now complete. They were now not only fierce and brave individually; they were also disciplined, well trained, and above all reliable at the unit level. And as such they would play a critical role at Cannae.

Psychologically, this was an army that had known nothing but the most decisive sort of success since it had entered Italy. In a life-and-death struggle, confidence is crucial, and the recent past had given these men every reason to believe in their own fighting skills, as well as their commander’s ability to drive opponents into positions of utter vulnerability and near helplessness. Many must have already killed Roman soldiers personally and must have also observed them reduced to an abject state, begging for mercy. That was Hannibal’s point when he reassured an officer worried about the size of the opposing force at Cannae. (“In all this multitude there is no one who is called Gisgo.”) For Carthaginians, more Romans simply meant more Romans to kill. This was the dark side of a truly professional fighting force, especially one that fought with edged weapons; they were used to killing, inured to it. They would kill without hesitation. It was a terrible advantage that the Carthaginians had and that most of the Romans at Cannae lacked.