To return to the war between Rome and Carthage, we must regard its first cause as being the indignation of Hamilcar surnamed Barcas, the actual father of Hannibal. Unvanquished in spirit by the war for Sicily, since he felt that he had kept the army at Eryx under his command combative and resolute until the end, and had only agreed to peace yielding to circumstances after the defeat of the Carthaginians in the naval battle, he maintained his resolve and waited for an opportunity to strike. Had not the mutinous outbreak among the mercenaries occurred, he would very soon, as far as it lay in his power, have created some other means and other resources for resuming the contest, but he was hampered by these civil disturbances which occupied all his time and attention.
When, on the suppression of this disturbance by the Carthaginians, the Romans announced their intention of making war on Carthage, the latter at first was ready to negotiate on all points, thinking that, justice being on her side, she would prevail; but as the Romans refused to negotiate, the Carthaginians had to yield to circumstances, and though deeply aggrieved they were powerless, and evacuated Sardinia, agreeing also to pay twelve hundred talents in addition to the sum previously exacted, in order not to be forced to accept war at that time. This, then, we must take to be the second and principal cause of the subsequent war; for Hamilcar, with the anger felt by all his compatriots at this last outrage added to his old indignation, as soon as he had finally crushed the mutiny of the mercenaries and secured the safety of his country, at once threw all his efforts into the conquest of Spain, with the object of using the resources thus obtained for the war against Rome. This success of the Carthaginian project in Spain must be held to be the third cause of the war, for relying on this increase of strength, they entered upon it with confidence. Of the fact that Hamilcar, although he died ten years before the beginning of the Second Punic War, contributed much to its origin many evidences can be found; but the anecdote I am about to relate suffices, I think, to confirm this.
At the time when Hannibal on his final defeat by the Romans had left his native land and was staying at the court of Antiochus, the Romans, who saw through the project of the Aetolians, sent an embassy to Antiochus, wishing to be fully aware what the king’s purpose was. The legates, as they saw that Antiochus was lending an ear to the Aetolians and was disposed to go to war with Rome, paid many attentions to Hannibal, wishing to make Antiochus suspicious of him, as in fact they succeeded in doing. For as time went on, the king’s mistrust of Hannibal grew ever more strong; and it fell out on one occasion that they came to have a talk about the alienation which had been secretly growing up between them. In the course of the conversation Hannibal defended himself on various grounds, and at length, being at a loss for further arguments, resorted to the following. He said that at the time when his father was about to start with his army on his expedition to Spain, he himself, then nine years of age, was standing by the altar, while Hamilcar was sacrificing to Zeus. When, on the omens being favourable, Hamilcar had poured a libation to the gods and performed all the customary rites, he ordered the others who were attending the sacrifice to withdraw to a slight distance and calling Hannibal to him asked him kindly if he wished to accompany him on the expedition. On his accepting with delight, and, like a boy, even begging to do it besides, his father took him by the hand, led him up to the altar, and bade him lay his hand on the victim and swear never to be the friend of the Romans. He begged Antiochus, then, now he knew this for a fact, as long as his intentions were hostile to Rome, to rely on him confidently and believe that he would have in him his sincerest supporter, but from the moment he made peace and alliance with her he had no need to wait for accusations but should mistrust and beware of him; for there was nothing he would not do against the Romans.
Antiochus, listening to this, thought he spoke genuinely and sincerely and in consequence abandoned all his former mistrust. However, we should consider this as an unquestionable proof of Hamilcar’s hostility and general purpose, and it is confirmed by the facts. For he made of his daughter’s husband Hasdrubal and his own son Hannibal such enemies of Rome that none could be more bitter. As Hasdrubal died before putting his purpose into execution, it was not in his case fully evident, but circumstances put it in the power of Hannibal to give only too manifest proof of his inherited hatred of Rome. Therefore, statesmen should above all take care that the true motives of the reconciliation of enmities and the formation of friendships do not escape them. They should observe when it is that men come to terms under pressure of circumstances and when owing to their spirit being broken, so that in the former case they may regard them as reserving themselves for a favourable opportunity and be constantly on their guard, and in the latter they may trust them as true friends and subjects and not hesitate to command their services when required.
We must consider, then, the causes of the Hannibalic War to have been those I have stated.
(Source: Polybius, The Histories, Vol.II, Book III, Loeb Classical Library)