Such was the condition of the AEtolians at the time of Philip's accession. Soon after that event we find them, under the leadership of Dorimachus, engaged in a series of freebooting expeditions in Messenia, and other parts of Peloponnesus. Aratus marched to the assistance of the Messenians at the head of the Achaean forces, but was totally defeated in a battle near Caphyae. The Achaeans now saw no hope of safety except through the assistance of Philip. That young monarch was ambitious and enterprising possessing considerable military ability and much political sagacity. He readily listened to the application of the Achaeans, and in 220 entered into an alliance with them. The war which ensued between the AEtolians on the one side, and the Achaeans, assisted by Philip, on the other, and which lasted about three years, has been called the Social War. Philip gained several victories over the AEtolians, but he concluded a treaty of peace with them in 217, because he was anxious to turn his arms against another and more formidable power. The great struggle now going on between Rome and Carthage attracted the attention of the whole civilized world. If was evident that Greece, distracted by intestine quarrels, must be soon swallowed up by whichever of those great states might prove successful; and of the two, the ambition of the Romans, who had already gained a footing on the eastern shores of the Adriatic was by far the more formidable to Greece. After the conclusion of the peace with the AEtolians Philip prepared a large fleet, which he employed to watch the movements of the Romans, and in the following year (216) he concluded a treaty with Hannibal, which, among other clauses, provided that the Romans should not be allowed to retain their conquests on the eastern side of the Adriatic. He even meditated an invasion of Italy, and with that view endeavoured to make himself master of Apollonia and Oricum. But though he succeeded in taking the latter city, the Romans surprised his camp whilst he was besieging Apollonia, and compelled him to burn his ships and retire. Meanwhile Philip had acted in a most arbitrary manner in the affairs of Greece; and when Aratus remonstrated with him respecting his proceedings, he got rid of his former friend and counsellor by means of a slow and secret poison (B.C. 213).