waived all claim to Amphipolis, in which his predecessor had placed a Macedonian garrison. The city was now left to itself; and the Athenians, had they been wise, would have spared no effort to secure it. As it was, they let slip a golden opportunity of regaining a position which might have been in their hands a barrier against the growing power of Macedon, and would have certainly enabled them to maintain their maritime supremacy on the Ægean.
Philip meanwhile, having freed himself for the present from the fear of Athens, was at liberty to fence off his kingdom from the attacks of its land enemies. He had already organised something of a military force, and with this he prepared to strike a decisive blow at the Illyrian, Pæonian, and Thracian tribes, which were perpetually crossing the Macedonian frontier in plundering expeditions. It seems that these tribes, which were scattered over what are now the provinces of Bosnia, Servia, and Albania, were at this time being pushed south wards by a great movement of the Gauls. The Illyrians were Macedon's most dangerous neighbours, and they had inflicted many a disastrous defeat on Philip's predecessors. Now they were at the height of their power, and were united for purposes of war under a chief named Bardylis, an able leader and a brave warrior. Philip, after thoroughly vanquishing the Pæonians, which he seems to have done easily, turned his arms against the more formidable Illyrians, and attacked them in western Macedonia, which they had invaded. He won a hard-fought battle, chiefly through the efficiency of his cavalry. The Illyrian
