Macedonia might have exercised an influence over the course of events more decisive than that of Syracuse. From the Eastern powers neither furtherance nor hindrance was for the moment to be expected. Antiochus the Great, the natural ally of Philip, had, after the decisive victory of the Egyptians at Raphia in 537, to deem himself fortunate in obtaining peace from the indolent Philopator on the basis of the status quo ante. The rivalry of the Lagidae and the constant apprehension of a renewed outbreak of the war on the one hand, and insurrections of pretenders in the interior and enterprises of all sorts in Asia Minor, Bactria, and the eastern satrapies on the other, prevented him from joining that great anti-Roman alliance which Hannibal had in view. The Egyptian court was decidedly on the side of Rome, with which it renewed alliance in 544; but it was not to be expected of Ptolemy Philopator, that he would support otherwise than by corn-ships. Accordingly there was nothing to prevent Greece and Macedonia from throwing a decisive weight into the great Italian struggle except their own discord; they might save the Hellenic name, if they had the self-control to stand by each other for but a few years against the common foe. Such sentiments doubtless were current in Greece. The prophetic saying of Agelaus of Naupactus, that he was afraid that the prize-fights in which the Hellenes now indulged at home might soon be over; his earnest warning to direct their eyes to the west, and not to allow a stronger power to impose on all the parties now contending a peace of equal servitude - such sayings had essentially contributed to bring about the peace between Philip and the Aetolians (537), and it was a significant proof of the tendency of that peace that the Aetolian league immediately nominated Agelaus as its strategus.
National patriotism was bestirring itself in Greece as in Carthage: for a moment it seemed possible to kindle a Hellenic national war against Rome. But the general in such a crusade could only be Philip of Macedonia; and he lacked the enthusiasm and the faith in the nation, without which such a war could not be waged. He knew not how to solve the arduous problem of transforming himself from the oppressor into the champion of Greece. His very delay in the conclusion of the alliance with Hannibal damped the first and best zeal of the Greek patriots; and when he did enter into the conflict with Rome, his mode of conducting war was still less fitted to awaken sympathy and confidence. His first attempt, which was made in the very year of the battle of Cannae (538), to obtain possession of the city of Apollonia, failed in a way almost ridiculous, for Philip turned back in all haste on receiving the totally groundless report that a Roman fleet was steering for the Adriatic. This took place before there was a formal breach with Rome; when the breach at length ensued, friend and foe expected a Macedonian landing in Lower Italy. Since 539 a Roman fleet and army had been stationed at Brundisium to meet it; Philip, who was without vessels of war, was constructing a flotilla of light Illyrian barks to convey his army across. But when the endeavour had to be made in earnest, his courage failed to encounter the dreaded quinqueremes at sea; he broke the promise which he had given to his ally Hannibal to attempt a landing, and with the view of still doing something he resolved to make an attack on his own share of the spoil, the Roman possessions in Epirus (540). Nothing would have come of this even at the best; but the Romans, who well knew that offensive was preferable to defensive protection, were by no means content to remain - as Philip may have hoped - spectators of the attack from the opposite shore. The Roman fleet conveyed a division of the army from Brundisium to Epirus; Oricum was recaptured from the king, a garrison was thrown into Apollonia, and the Macedonian camp was stormed. Thereupon Philip passed from partial action to total inaction, and notwithstanding all the complaints of Hannibal, who vainly tried to breathe into such a halting and shortsighted policy his own fire and clearness of decision, he allowed some years to elapse in armed inactivity.
Nor was Philip the first to renew the hostilities. The fall of Tarentum (542), by which Hannibal acquired an excellent port on the coast which was the most convenient for the landing of a Macedonian army, induced the Romans to parry the blow from a distance and to give the Macedonians so much employment at home that they could not think of an attempt on Italy. The national enthusiasm in Greece had of course evaporated long ago. With the help of the old antagonism to Macedonia, and of the fresh acts of imprudence and injustice of which Philip had been guilty, the Roman admiral Laevinus found no difficulty in organizing against Macedonia a coalition of the intermediate and minor powers under the protectorate of Rome. It was headed by the Aetolians, at whose diet Laevinus had personally appeared and had gained its support by a promise of the Acarnanian territory which the Aetolians had long coveted. They concluded with Rome a modest agreement to rob the other Greeks of men and land on the joint account, so that the land should belong to the Aetolians, the men and moveables to the Romans. They were joined by the states of anti-Macedonian, or rather primarily of anti-Achaean, tendencies in Greece proper; in Attica by Athens, in the Peloponnesus by Elis and Messene and especially by Sparta, the antiquated constitution of which had been just about this time overthrown by a daring soldier Machanidas, in order that he might himself exercise despotic power under the name of king Pelops, a minor, and might establish a government of adventurers sustained by bands of mercenaries. The coalition was joined moreover by those constant antagonists of Macedonia, the chieftains of the half-barbarous Thracian and Illyrian tribes, and lastly by Attalus king of Pergamus, who followed out his own interest with sagacity and energy amidst the ruin of the two great Greek states which surrounded him, and had the acuteness even now to attach himself as a client to Rome when his assistance was still of some value.
It is neither agreeable nor necessary to follow the vicissitudes of this aimless struggle. Philip, although he was superior to each one of his opponents and repelled their attacks on all sides with energy and personal valour, yet consumed his time and strength in that profitless defensive. Now he had to turn against the Aetolians, who in concert with the Roman fleet annihilated the unfortunate Acarnanians and threatened Locris and Thessaly; now an invasion of barbarians summoned him to the northern provinces; now the Achaeans solicited his help against the predatory expeditions of Aetolians and Spartans; now king Attalus of Pergamus and the Roman admiral Publius Sulpicius with their combined fleets threatened the east coast or landed troops in Euboea. The want of a war fleet paralyzed Philip in all his movements; he even went so far as to beg vessels of war from his ally Prusias of Bithynia, and even from Hannibal. It was only towards the close of the war that he resolved - as he should have done at first - to order the construction of 100 ships of war; of these however no use was made, if the order was executed at all. All who understood the position of Greece and sympathized with it lamented the unhappy war, in which the last energies of Greece preyed upon themselves and the prosperity of the land was destroyed; repeatedly the commercial states, Rhodes, Chios, Mitylene, Byzantium, Athens, and even Egypt itself had attempted a mediation. In fact both parties had an interest in coming to terms. The Aetolians, to whom their Roman allies attached the chief importance, had, like the Macedonians, much to suffer from the war; especially after the petty king of the Athamanes had been gained by Philip, and the interior of Aetolia had thus been laid open to Macedonian incursions. Many Aetolians too had their eyes gradually opened to the dishonourable and pernicious part which the Roman alliance condemned them to play; a cry of horror pervaded the whole Greek nation when the Aetolians in concert with the Romans sold whole bodies of Hellenic citizens, such as those of Anticyra, Oreus, Dyme, and Aegina, into slavery. But the Aetolians were no longer free; they ran a great risk if of their own accord they concluded peace with Philip, and they found the Romans by no means disposed, especially after the favourable turn which matters were taking in Spain and in Italy, to desist from a war, which on their part was carried on with merely a few ships, and the burden and injury of which fell mainly on the Aetolians. At length however the Aetolians resolved to listen to the mediating cities: and, notwithstanding the counter-efforts of the Romans, a peace was arranged in the winter of 548-9 between the Greek powers. Aetolia had converted an over-powerful ally into a dangerous enemy; but the Roman senate, which just at that time was summoning all the resources of the exhausted state for the decisive expedition to Africa, did not deem it a fitting moment to resent the breach of the alliance. The war with Philip could not, after the withdrawal of the Aetolians, have been carried on by the Romans without considerable exertions of their own; and it appeared to them more convenient to terminate it also by a peace, whereby the state of things before the war was substantially restored and Rome in particular retained all her possessions on the coast of Epirus except the worthless territory of the Atintanes. Under the circumstances Philip had to deem himself fortunate in obtaining such terms; but the fact proclaimed - what could not indeed be longer concealed - that all the unspeakable misery which ten years of a warfare waged with revolting inhumanity had brought upon Greece had been endured in vain, and that the grand and just combination, which Hannibal had projected and all Greece had for a moment joined, was shattered irretrievably.