If you have ever looked at a map of the Roman Empire at its height in the early 2nd century AD, you will note that it surrounded the entire Mediterranean Sea, while stretching north and west into modern-day Germany, France, Belgium and Britain. To the east, it embraced Greece, Albania, Bulgaria, Croatia and Serbia, to name but a few. At the end of the 3rd century BC, however, the situation was very different.

By around 264 BC, the city of Rome controlled much of the Italian peninsula south of the River Po, having spent a century waging war against its numerous city-states. Following the First Punic War, Rome gained control of much of Sicily and, shortly afterwards, Sardinia. But another, imperial adversary stood in the way of its expansionist ambitions.

Carthage

The city-state of Carthage, near modern-day Tunis, controlled, through alliances and force of arms, much of the northern coastline of Africa, including; the territories corresponding roughly to Tunisia, Algeria, Morocco and Libya. Its influence also extended further afield to Corsica and the Balearic Islands. But its greatest prize was Iberia.

Through its two strategic centres of Gades (modern-day Cádiz) and New Carthage (Cartagena) it controlled much of the south of the great peninsula, corresponding approximately to today’s Andalusia, as well as territory stretching up the eastern coastline as far as the River Ebro.

Much of Iberia had been conquered by the Barca family, whose most famous son was Hannibal, the legendary Carthaginian general who would go on to inflict a series of devastating defeats on the Roman legions, culminating in the catastrophe at Cannae, where somewhere between 50,000 and 80,000 Romans are believed to have been killed.

Hannibal understood that Rome’s ambition would never be satisfied and that its envious eyes would soon turn towards the rich territories of Spain. He therefore resolved to strike first. But before he could do so, he needed to secure his rear.

Saguntum, just north of today’s Valencia, was a wealthy and independent city. Its alliance with Rome, however, represented a military threat. Hannibal could not tolerate a settlement hostile to Carthaginian interests that might one day provide Rome with a foothold to use as a secure base for its operations.

In 219 BC, he was presented with the pretext he needed. Tensions had escalated when Saguntum became involved in disputes with Iberian tribes allied to Carthage. Hannibal intervened and, after a months-long siege, captured and destroyed the city. It was a direct provocation to Rome and Rome duly responded.

Hannibal’s Gamble

Knowing that Rome controlled the sea, the senate assumed correctly that Hannibal’s army would be forced to take the long and difficult land route to invade Italy. What they badly underestimated was the speed with which he would do so. Rome’s strategy for the war with Carthage was twofold. Two consular armies were formed. The first, under the consul Tiberius Sempronius Longus, was to invade North Africa and attempt to gain allies there. The second, commanded by Publius Cornelius Scipio – father of the future Scipio Africanus – was to invade Iberia, using Rome’s allied Greek city of Massilia (modern-day Marseille) as a base and disrupt Carthage’s greatest source of wealth and manpower for its armies.

Hannibal knew that speed was his key to catching the Roman legions by surprise. Setting out from New Carthage with his army, he reached the river Ebro, a march of 325 miles in a matter of weeks. He then embarked on a lightning campaign lasting roughly a month, subduing the hostile tribes of north-eastern Iberia.

Leaving behind a force of around 10,000 troops to control the area and guard the huge quantities of supplies he would need, Hannibal continued north. His brother, Hasdrubal, left in command of Iberia, was expected to follow him to Italy the following year with a reinforcing army.

Hannibal’s route would take him across the Pyrenees, then northeast towards the great River Rhône. Before undertaking the seemingly impossible crossing of the Alps.

Meanwhile, Scipio had been delayed by the need to raise a fresh army. He finally arrived at Massilia, at the mouth of the Rhône, in July or August 218 BC. He sought intelligence from the Massiliots, who knew the region well. More importantly, he still believed that Hannibal had yet to cross the Pyrenees.

It must therefore have come as a considerable shock to be informed that the Carthaginians  had already crossed the mountains. Concluding, however, that Hannibal must still be several days away from the Rhône, Scipio dispatched a force of 300 heavy cavalry, accompanied by local guides, to locate the enemy army.

Hannibal, who had already reached the Rhône, was himself shocked to learn that a Roman army had arrived on the coast. It is a striking illustration of the limitations of military intelligence in that period. He too dispatched scouts: a force of around 500 Numidian light cavalry.

The two mounted forces soon encountered one another. According to Roman sources, the Numidians were heavily defeated and driven from the field. Others believe, it is perhaps more likely that the fleet and lightly armed Africans simply disengaged and withdrew, as they were expert at doing.

The Romans pursued them and discovered the Carthaginian camp. They immediately returned at speed to inform Scipio. The Roman consul now faced a decision.

Scipio’s Choice

Scipio realised that he could not continue on to Spain while Hannibal’s army was advancing towards Italy. He must attempt to stop the Carthaginians before they cross the Rhône. Quickly disembarking his army, and leaving the bulk of his stores aboard the ships, he advanced north along the river valley.

After several days of marching, Scipio located Hannibal’s camp. But the Carthaginian army had disappeared. Without adequate supplies of food and equipment, and knowing that an attempt to forage for provisions would only slow him down, Scipio had little choice but to abandon the pursuit and return to Massilia. Hannibal had evaded him.

So what should he do now? Scipio’s orders from the Senate had been clear. He was to take his army to Iberia and carry the war directly to Carthage’s interests there. But he now understood that Hannibal and his army represented the greatest immediate threat to Rome — and he had failed to stop them. There was another consideration, too. Defeating Carthage’s greatest general would bring him and his family great renown, travelling on to Iberia was now, to his mind, a side show.

Scipio therefore compromised. He handed command of the consular army to his brother, Gnaeus Cornelius Scipio, already an experienced general, who had been serving as his second-in-command, ordering him to continue to Iberia. Publius himself would return to northern Italy, take command of the legions there and confront Hannibal as his army descended, battered and exhausted, from the Alps. It was a decision that would have enormous consequences.

Gnaeus Scipio Opens a Second Front

In the autumn of 218 BC, Gnaeus Scipio landed at Emporion, on the east coast below the Pyrenees. The settlement was a Greek colony established by Massilia and provided the Romans with an important stronghold.

Gnaeus moved quickly. Swiftly subduing the local tribes and establishing coastal garrisons, he secured Roman control of the area. With his position consolidated — and supported by a considerable new auxiliary force from the defeated tribes — he moved inland to confront the Carthaginian force that Hannibal had left behind under the command of an officer called Hanno.

Realising too late that a large Roman force had landed in the northeast and that outmatched his own in numbers, Hanno withdrew inland towards a settlement called Cissa, where he established strong fortifications.

Yet, rather than remain behind his defences and wait for reinforcements to arrive from the south under Hasdrubal, Hanno made a critical mistake. Despite his own force being numerically inferior he marched out onto open ground to confront the Romans.

Gnaeus Scipio swiftly defeated him and Hanno was captured, along with the supplies Hannibal had painstakingly accumulated for the planned reinforcing Carthaginian army. When Hasdrubal heard that the Romans had landed, he raced north with a force of around 8,000 infantry and 1,000 cavalry.

But, as Hannibal had previously caught the Romans off guard with the speed of his advance, Hasdrubal was now fell short by the speed of Gnaeus Scipio’s invasion.

By the time he reached Cissa, the battle was already over, the corpses of the dead littering the field.

Although Hasdrubal stayed to inflict significant damage on Roman interests in the north, and used Carthage’s strong relationships with local tribes – particularly the Ilergetae, to rebel against Rome – he could not drive the legions from their foothold and was forced to withdraw south of the River Ebro.

The Battle for Time

While Gnaeus consolidated his position in Iberia, Hannibal arrived in the Po valley in northern Italy. The Romans were astonished at his swift arrival and rushed to meet him. At successive engagements, however, Hannibal destroyed all before him in battles at Ticinus, where Publius Scipio was wounded, at Trebia and later a devastating loss at Lake Trasimene, where 15,000 legionaries were killed including Consul Flaminius, the very general who was to take the war to Carthage in north Africa. However, despite these disasters, and there would be more, the big advantage that Rome had over Hannibal was its ability to raise new armies. Hannibal’s original strategy had depended not simply upon defeating Roman armies, but upon maintaining momentum and being reinforced by Carthaginian troops from Iberia. Instead he was now forced to seek men elsewhere, from the unreliable Gaulish tribes and by attempting to loosen the ties of the Italian city states with Rome. However, despite his stunning victory at Cannae, over the coming years he gradually found himself isolated.

It would not be until 207 BC — eleven years after his brother had crossed the Alps — that Hasdrubal finally succeeded in bringing a major army through the Alpine passes and into Italy. By then, however, the strategic picture had changed. The legions were now highly experienced and increasingly more adaptable when facing Hannibal’s forces. Hannibal himself had been pushed into the south of the Italian peninsula, unable to break out. The opportunity that might have existed in 218 BC was diminished.

The Decision that Changed History?

It is impossible to know with certainty what would have happened had Publius Scipio simply followed his original orders and continued to Iberia. History does not provide us with alternate outcomes. But the strategic danger is clear.

Had Publius Scipio not sent his brother ahead with his legions and not established the Roman foothold there, Hasdrubal would certainly have been able to reinforce Hannibal sooner. Had that occurred at the height of his success, when Rome had already suffered catastrophic defeats, the consequences could have been extraordinary. The Roman senate itself might have been forced to seek terms.

Perhaps, then, the empire that would eventually come to dominate the Mediterranean would have been Carthage, with Rome just another jumped up city state and a footnote in history.

Alistair Tosh is a novelist and the author of the Edge of Empire series and the new trilogy, The Lion and the Eagle, of which the first in the series The Sons Of Carthage is out now and available to purchase.