Second Punic War

Cannae brought the Roman Republic to the brink of collapse. In less than three years, Rome had lost more than 120,000 men. Major southern Italian cities, most notably Capua, defected to the Carthaginian side, and the conflict rapidly expanded across the Mediterranean. Syracuse in Sicily and the kingdom of Macedonia allied with Carthage, while Carthaginian forces attempted, though ultimately failed, to seize Roman-held Sicily and Sardinia. To survive, Rome had to reinvent its entire approach to mobilization. The Senate took the unprecedented step of enrolling slaves, criminals, and citizens who fell far below the traditional property qualifications into the legions, vastly increasing the number of men under arms. Rather than meeting Hannibal in another pitched battle, the Romans adopted a strategy of containment in Italy, slowly besieging and recapturing the rebellious Italian cities while refusing to engage Hannibal directly.

While Hannibal remained undefeated but increasingly isolated in southern Italy, the true strategic turning point of the war was unfolding in Iberia. Rome had established a tenuous lodgement in the northeast of the peninsula in 218 BCE. For years, the fighting there swayed back and forth, but in 211 BCE, the Roman forces suffered a catastrophic defeat. It was then that a young, charismatic patrician named Publius Cornelius Scipio was given the Iberian command. In 209 BCE, Scipio launched a daring amphibious assault to capture Carthago Nova, the administrative heart and chief treasury of the Carthaginians in Iberia. Scipio studied Hannibal's tactics and adapted them. In 208 BCE, he defeated Hannibal’s brother, Hasdrubal, at Baecula. Though Hasdrubal managed to slip away with the remnants of his army, crossing the Alps in 207 BCE to reinforce his brother in Italy, this second Carthaginian invasion was decisively crushed by the Romans at the Battle of the Metaurus before the brothers could link up. Back in Iberia, Scipio delivered the final blow at the Battle of Ilipa in 206 BCE, permanently extinguishing Carthaginian rule in the peninsula and depriving Carthage of its primary source of silver and mercenary recruits.

With Iberia secured, Scipio proposed a bold plan to end the war: a direct invasion of the Carthaginian homeland. Landing in North Africa in 204 BCE, Scipio allied with disgruntled Numidian kingdoms and began ravaging the countryside, threatening Carthage itself. Terrified, the Carthaginian Senate had no choice but to recall Hannibal from Italy, where he had spent fifteen fruitless years waiting for reinforcements that never came. The two greatest generals of the age finally met in 202 BCE at the Battle of Zama, a flat plain southwest of Carthage. Hannibal relied on his remaining war elephants and his veteran infantry, but Scipio had neutralized the elephant threat by leaving open lanes in his infantry lines for the beasts to pass through harmlessly. Crucially, the superior Numidian cavalry was now on the Roman side. When the Roman and Numidian horsemen swept back to strike Hannibal's veterans in the rear, the battle was decided. Hannibal was defeated, and Carthage was forced to sue for peace.

The peace terms of 201 BCE stripped Carthage of its empire, leaving it a client state of Rome. It surrendered all overseas territories, was forced to pay a crushing indemnity of ten thousand silver talents over fifty years, and was forbidden from waging war outside of Africa—and within Africa, only with Rome's permission. The western Mediterranean was now indisputably Roman. Though Carthage would recover commercially, its political independence was gone forever. Decades later, Rome would use a minor border dispute between Carthage and the Numidians as a pretext to launch the Third Punic War in 149 BCE, culminating in 146 BCE with the total destruction of the city. The Second Punic War was the crucible of the Roman Empire; by surviving the genius of Hannibal, Rome forged the military machine, the administrative resilience, and the ruthless geopolitical doctrine that would allow it to dominate the ancient world for centuries to come.