Reasons for the proposed invasion of Macedon.

Besides this, however, there was another justification, namely, that of necessity. Although Pyrrhus had been compelled to withdraw from Italy, he had not returned by any means alone, but had brought quite a large army with him, consisting of many thousands of men, all of whom must now be fed and paid. All the resources of his own kingdom had been wellnigh exhausted by the drafts which he had made upon them to sustain himself in Italy, and it was now necessary, he thought, to embark in some war, as a means of finding employment and subsistence for these troops. He determined, therefore, on every account, to make a foray into Macedon.

Before setting off on his expedition, he contrived to obtain a considerable force from among the Gauls as auxiliaries. Antigonus, also, had Gauls in his service, for they themselves were divided, as it would seem, in respect both to their policy and their leaders, as well as the Macedonians; and Antigonus, taking advantage of their dissensions, had contrived to enlist some portion of them in his cause, while the rest were the more easily, on that very account, induced to join the expedition of Pyrrhus. Things being in this state, Pyrrhus, after completing his preparations, commenced his march, and soon crossed the Macedonian frontier.

In the outset Pyrrhus is successful.
The country is disposed to submit to him.

As was usually the case with the enterprises which he engaged in, he was, in the outset, very successful. He conquered several cities and towns as he advanced, and soon began to entertain higher views in respect to the object of his expedition than he had at first formed. Instead of merely plundering the frontier, as he had at first intended, he began to think that it would be possible for him to subdue Antigonus entirely, and reannex the whole of Macedon to his dominions. He was well known in Macedon, his former campaigns in that country having brought him very extensively before the people and the army there. He had been a general favorite, too, among them at the time when he had been their ruler; the people admired his personal qualities as a soldier, and had been accustomed to compare him with Alexander, whom, in his appearance and manners, and in a certain air of military frankness and generosity which characterized him, he was said strongly to resemble. Pyrrhus now found, as he advanced into the country of Macedonia, that the people were disposed to regard him with the same sentiments of favor which they had formerly entertained for him. Several of the garrisons of the cities joined his standard; and the detachments of troops which Antigonus sent forward to the frontier to check his progress, instead of giving him battle, went over to him in a body and espoused his cause. In a word, Pyrrhus found that, unexpectedly to himself, his expedition, instead of being merely an incursion across the frontiers on a plundering foray, was assuming the character of a regular invasion. In short, the progress that he made was such, that it soon became manifest that to meet Antigonus in one pitched battle, and to gain one victory, was all that was required to complete the conquest of the country.

Combat in the mountain defile.

He accordingly concentrated his forces more and more, strengthened himself by every means in his power, and advanced further and further into the interior of the country. Antigonus began to retire, desirous, perhaps, of reaching some ground where he could post himself advantageously. Pyrrhus, acting with his customary energy, soon overtook the enemy. He came up with the rear of Antigonus's army in a narrow defile among the mountains; at least, the place is designated as a narrow defile by the ancient historian who narrates these events, though, from the number of men that were engaged in the action which ensued, as well as from the nature of the action itself, as a historian describes it, it would seem that there must have been a considerable breadth of level ground in the bottom of the gorge.

Account of the phalanx.

The main body of Antigonus's troops was the phalanx. The Macedonian phalanx is considered one of the most extraordinary military contrivances of ancient times. The invention of it was ascribed to Philip, the father of Alexander the Great, though it is probable that it was only improved and perfected, and brought into general use, but not really originated by him. The single phalanx was formed of a body of about four thousand men. These men were arranged in a compact form, the whole body consisting of sixteen ranks, and each rank of two hundred and fifty-six men. These men wore each a short sword, to be used in cases of emergency, and were defended by large shields. The main peculiarity, however, of their armor, and the one on which the principal power of the phalanx depended as a military body, was in the immensely long spears which they carried. These spears were generally twenty-one, and sometimes twenty-four feet long. The handles were slender, though strong, and the points were tipped with steel. The spears were not intended to be thrown, but to be held firmly in the hands, and pointed toward the enemy; and they were so long, and the ranks of the men were so close together, that the spears of the fifth rank projected several feet before the men who stood in the front rank. Thus each man in the front rank had five steel-pointed spears projecting to different distances before him, while the men who stood in ranks further behind rested their spears upon the shoulders of those who were before them, so as to elevate the points into the air.

Its terrible efficacy.
Impossibility of making any impression upon it.