Immediately after the battle of Cannæ, Philip III. of Macedon had sent ambassadors to Hannibal, and had concluded a treaty, which fell, by chance, into the hands of the Romans. Even without this accident, it could not have been kept secret, not at least for any length of time. By this treaty, of which we certainly read in Polybius a genuine text, and of which the form is not at all Greek, but quite foreign, undoubtedly Carthaginian, the two states had not after all bound themselves to much. Hannibal secured to Philip in case of victory, that the Romans were to give up their possessions beyond the Adriatic, Corcyra, Apollonia, Epidamnus, the colony of Pharus, the Atintanians (an Epirote people), Dimalus, and the Parthinian Illyrians; and in return for this, Philip was to let the Carthaginians have the supremacy over Italy. Had Philip then been what he became in his riper years, this alliance would have proved dangerous to the Romans. But they, with that perseverance and heroic courage which distinguished them in the whole war, sent out a fleet under the prætor M. Valerius Lævinus, to protect Illyria, and to raise a party against him in Greece. Hostilities began in the year 537, or 538 (Lævinus not being a consul, the commencement is not quite certain), and the war lasted until the peace of P. Sempronius 548. This war was carried on very sluggishly on the side of the Romans, and Philip, who had to limit his exertions only to the few points on the mainland of Illyria, could have made himself master of these, had he not managed his affairs quite as feebly. His conduct then gives us quite a different idea of his powers from that which we are led to form afterwards. Had he given to Hannibal but ten thousand Macedonians as auxiliaries, Rome would have been in a sad plight; but he was too vain to do so.