Death of Philip and Accession of Alexander.—His Wars with the Thracians. It is said that Philip died14 when Pythodemus was archon at Athens,15 and that his son Alexander,16 being then 9about twenty years of age, marched into Peloponnesus17 as soon as he had secured the regal power. There he assembled all the Greeks who were within the limits of Peloponnesus,18 and asked from them the supreme command of the expedition against the Persians, an office which they had already conferred upon Philip. He received the honour which he asked from all except the Lacedaemonians,19 who replied that it was an hereditary custom of theirs, not to follow others but to lead them. The Athenians also attempted to bring about some political change; but they were so alarmed at the very approach of Alexander, that they conceded to him even more ample public honours than those which had been bestowed upon Philip.20 He then returned into Macedonia and busied himself in preparing for the expedition into Asia.
However, at the approach of spring (b.c. 335), he marched towards Thrace, into the lands of the Triballians and Illyrians,21 because he ascertained that these nations were meditating a change of policy; and at the same time, as they were lying on his frontier, he thought it inexpedient, when he was about to start on a campaign so far away from his own land, to leave them behind him 10without being entirely subjugated. Setting out then from Amphipolis, he invaded the land of the people who were called independent Thracians,22 keeping the city of Philippi and mount Orbelus on the left. Crossing the river Nessus,23 they say he arrived at mount Haemus24 on the tenth day. Here, along the defiles up the ascent to the mountain, he was met by many of the traders equipped with arms, as well as by the independent Thracians, who had made preparations to check the further advance of his expedition by seizing the summit of the Haemus, along which was the route for the passage of his army. They had collected their waggons, and placed them in front of them, not only using them as a rampart from which they might defend themselves, in case they should be forced back, but also intending to let them loose upon the phalanx of the Macedonians, where the mountain was most precipitous, if they tried to ascend. They had come to the conclusion25 that the denser the phalanx was with which the waggons rushing down came into collision, the more easily would they scatter it by the violence of their fall upon it.
But Alexander formed a plan by which he might cross the mountain with the least danger possible; and since he was resolved to run all risks, knowing that there were no means of passing elsewhere, he ordered the heavy-armed soldiers, as soon as the waggons began to rush down the declivity, to open their ranks, and directed that those whom the road was sufficiently wide to permit 11to do so should stand apart, so that the waggons might roll through the gap; but that those who were hemmed in on all sides should either stoop down together or even fall flat on the ground, and lock their shields compactly together, so that the waggons rushing down upon them, and in all probability by their very impetus leaping over them, might pass on without injuring them. And it turned out just as Alexander had conjectured and exhorted. For some of the men made gaps in the phalanx, and others locked their shields together. The waggons rolled over the shields without doing much injury, not a single man being killed under them. Then the Macedonians regained their courage, inasmuch as the waggons, which they had excessively dreaded, had inflicted no damage upon them. With a loud cry they assaulted the Thracians. Alexander ordered his archers to march from the right wing in front of the rest of the phalanx, because there the passage was easier, and to shoot at the Thracians where they advanced. He himself took his own guard, the shield-bearing infantry and the Agrianians,26 and led them to the left. Then the archers shot at the Thracians who sallied forward, and repulsed them; and the phalanx, coming to close fighting, easily drove away from their position men who were light-armed and badly equipped barbarians. The consequence was, they no longer waited to receive Alexander marching against them from the left, but casting away their arms they fled down the mountain as each man best could. About 1,500 of them were killed; but only a few were taken prisoners on account of their swiftness of foot and acquaintance with the country. However, all the women who were accompanying them were captured, as were also their children and all their booty.