The battle of the Aegates Islands was the final and decisive battle of the First Punic War. When the war had started twenty years earlier, Roman had been a land power and Carthage the foremost naval power in the western Mediterranean. Now that war would end with a resounding Roman naval victory.
The Romans had won the majority of the naval battles that had taken place during the war, but they had suffered a series of major disasters, losing four major fleets in storms. In 249 B.C. they had lost part of their fleet in their only major naval defeat of the war, the battle of Drepanum, and had then lost the rest of the fleet in yet another storm. For the next seven years they made no effort to rebuild their fleet. The main reason for this was financial exhaustion. The Roman state could not afford to both keep its armies in the field and to build a new fleet. The Romans chose to keep their armies in the field, and maintained a siege of Lilybaeum, the main Carthaginian base remaining on Sicily, that lasted from 250 B.C. to the end of the war.
After more than six years it became clear that the Roman armies were not able to finish the war on Sicily. In 247 B.C. Carthage had sent Hamilcar Barca to command on Sicily, and although he was unable to break the Roman grip on Lilybaeum, or indeed capture any significant Roman possession, he conducted an active guerrilla war on Sicily, and was even able to launched limited raids on the Italian coast.
Faced with this stalemate the Senate decided to make one final attempt to win the war at sea. With public funds exhausted, the Senate decided to impose a heavy loan on the wealthiest men of the state, which would be paid back if the Romans won. Most of the wealthy men involved were of course in the Senate, although trade had started to become important in Rome since the conquest of the Greek cities of southern Italy in the years before the outbreak of the war.
With no tradition of ship building, all of the Roman fleets had been based on copies of captured Carthaginian ships. According to Polybius this new fleet was built on a new model, copying a blockade runner captured at Lilybaeum. This ship had apparently been owned by a Carthaginian called Hannibal of Rhodes, suggesting that the design of the ship might have owed something to that island. In the event the design of the ships does not appear to have played a significant part in the Roman victory.
Far more significant was complacency in Carthage. In 249 they had maintained their fleet at Drepanum. By 242, seven years after the destruction of the last Roman fleet, Carthage had pulled her fleet home, and dismissed her experienced crews.
In the summer of 242 the new Roman fleet, under the command of the consul Lutatius Catulus, sailed to Sicily. Finding no Carthaginian fleet, he landed troops at Drepanum to besiege the place, and then concentrated on training his sailors. Catulus would be given some nine months to turn his inexperienced sailors into expert sailors.
Carthage responded by recruiting new crews for their ships. In the spring of 241 the fleet was finally ready to sail, under the command of a admiral named Hanno (as were many other Carthaginian generals and admirals of this war). His fleet was burdened with supplies for the besieged garrisons on Sicily. Hanno’s plan was to sail across to the Aegates Islands, west of Sicily, and from there make a dash to Hamilcar Barca’s base at Eryx. Once there he would unload the supplies, take onboard the most experienced of Hamilcar’s mercenaries, and attack the Roman fleet.
Catulus decided to prevent this. The long period of training now paid off. On the day of the battle the wind was blowing from the west, offering help to Hanna’s fleet and making it more difficult for the Romans to stay together. Bad weather had after all cost the Romans four previous fleets. This time the Roman sailors were up to the task, and were able to form up in line of battle, forcing Hanna to fight a battle under the least favourable circumstances.
The fighting was predictably one sided. Catulus’s battle-ready ships with their experienced crews and carefully selected marines inflicted a crushing defeat on Hanno’s heavily burdened ships and their inexperienced crews. Polybius recorded the Carthaginian losses as 50 ships sunk and 70 captured. Hanno was executed for his failure in the battle.
In the aftermath of this defeat, Carthage decided to negotiate. Hamilcar was given the authority to make peace. Catulus agreed to fairly generous terms. Carthage would evacuate Sicily. Neither Rome nor Carthage would make war on the others allies. Carthage would pay Rome an indemnity of 2,200 talents, which would just cover the cost of the final Roman fleet. In Rome these terms were considered to be too generous, but commissions sent from Rome only made minor changes, adding another 1,000 talents to the payment and forbidding Punic war-ships from entering Italian waters. This version of the treaty was accepted by both sides, and the First Punic War came to an end after over twenty years.