Mardonius had constructed an entrenched camp on the north or left bank of the river Asopus. In front of this camp he drew up his line of battle. The Greek army, which was under the command of Pausanias, uncle of one of the kings of Sparta and regent, took up its position on the slopes of Mount Cithæron. Their unwillingness to descend into the plain and come to close quarters emboldened Mardonius to attack them with his cavalry. The contingent from Megara happened to be in a peculiarly advanced or otherwise exposed situation, and suffered so severely that it had to send for help. It explains Pausanias's apparent timidity when we find that he could not induce any of his troops to go to the assistance of their hard-pressed countrymen. In the end three hundred Athenians volunteered for this service. They took with them a force of archers, an arm in which Megarians were entirely deficient. Some sharp fighting ensued; at last an arrow killed the horse of the Persian general Masistius, and the general, a man of great stature and beauty, and a splendid figure in his gilded chain-armour, was thrown to the ground. This happened close to the Athenian lines, and Masistius was soon killed, though it was only by a thrust in the eye that he could be despatched, so impenetrable was his armour. The Persian cavalry, as soon as it became aware of its leader's fate, charged furiously to recover the body. For a time the Greeks were driven back, but they rallied and recovered the prize. The Persians, demoralised, in the usual fashion of Asiatics, by the loss of their leader, retreated in disorder.
Encouraged by this success, the Greeks descended into the plain, and took up a second position on the right bank of the Asopus. The Lacedæmonians occupied the right wing, the Athenians the left. A curious instance of the want of discipline in the army is afforded by the dispute which arose between the Athenians and the Tegeans as to precedence. The first post of honour, the right wing, was conceded by common consent to the Lacedæmonians; the second part, the left wing, was the matter in dispute. Tegea claimed it on account of various mythical exploits, and on more recent successes achieved in company with Sparta. Athens had also its mythical claims, but it relied on the victory at Marathon. The decision was given in favour of Athens by a general vote of the Lacedæmonian soldiery. The new position taken up by the Greeks was found to be anything but convenient. The army suffered from a scarcity of water; it was unsafe to approach the river banks, for this was commanded by the Persian archers, and consequently the sole supply was a spring, known by the name of Gargaphia, which was close to the Lacedæmonian position. Mardonius shifted his line of battle a little to the west, so as to front the new Greek position. His picked native troops, the Persians and the Sacæ (Turkomans) were posted, not in the centre, the post of honour in an Asiatic army, as we have seen more than once before, but on the left wing, where they would face the Spartans; to the Theban contingent was allotted a place on the right where they were opposed to their old enemies of Athens. This was done at the suggestion of the Theban leaders, and the suggestion did credit, as we shall see, to their sagacity.
For ten days the two armies remained in position without moving. The soothsayers on both sides reported that the sacrifices portended success to a policy of defence; disaster, if an attack should be attempted. It was to the Greek cause that the delay was more perilous. The army suffered greatly from the incessant attacks of the Persian cavalry; the scanty water supply was a great inconvenience and even a danger; and when, at the suggestion of his Theban friends, Mardonius sent his cavalry to cut off the supplies that were sent by the passes of Cithæron into the Greek camp, the dangers of the situation were still further aggravated. But the most serious peril of all was of another kind. The spirit of party, without which no free state can exist, but by which every free state is ultimately ruined, was rife in the Greek ranks. The traitors who had shown the signal of the shield after Marathon were not absent from the ranks at Platæa. The Thebans, with malignant sagacity, suggested to Mardonius that he should rely on the influences that were working for him, and avoid a general engagement. Happily for Greece, he refused their advice, which was discreditable, he said, to Persian honour. A people so superior in war had no need to resort to such expedients. He resolved to assume the offensive.
The Greeks were apprised of this change of plan by a visitor from the Persian camp. After nightfall, Alexander, King of Macedonia, who claimed to be descended from the great hero Achilles, rode up to the Athenian outposts and demanded speech with the generals. They were fetched by the guard, and he told them that Mardonius had tried in vain to obtain from the sacrifices signs that promised success, but that, nevertheless, he was determined to attack. "Be prepared," he went on, "and if you prevail, do something for my freedom; I have risked my life for love of Greece, to save you from a surprise by the barbarians. I am Alexander of Macedon."
When Pausanias heard the news he made a proposition to the Athenian generals, which, as coming from a Spartan, a race so punctilious in military honour, sounds very strange. He suggested that they should take the place of the Spartans on the right wing, where they would be opposed to the Persian infantry whom they had already conquered at Marathon, but whom the Spartans had never met in battle. The Athenians promptly agreed, but the movement was detected by Mardonius, and was met by a corresponding change in his line. On perceiving this, Pausanias reverted to the former arrangement.
The first offensive movement on the part of Mardonius was eminently successful. His cavalry got past, or broke through the Spartan line, so as to get at the spring of Gargaphia. This they choked, and so deprived the Greek army of their only available water supply.
A change of position became necessary. The new ground which the council of war determined to occupy was near Platæa, and went by the name of the Island, because it lay between two small streams which descend from Cithæron. The army would have a water supply, and would be protected, in a degree, from the Persian cavalry. It was then too late to make the movement, which would not be practicable except under cover of darkness. The whole of the next day had to be spent in extreme discomfort; and when at nightfall orders were given for a change of position, two somewhat alarming incidents took place. The centre of the Greek force, comprising all the smaller contingents, had been so demoralised, it would seem, by the troubles of the day that, as soon as the night fell, they marched off, not to the Island, but beyond it, to a place which they very probably considered to be better protected against the harassing attacks of the cavalry. This was the town of Platæa itself. They took up a position in front of the temple of Heré, a building of considerable size, as we know from the ruins still to be seen, and on high ground. Here they had the town behind them, and ground, unfavourable to the action of cavalry on either side. The other disconcerting event was the conduct of one of the Spartan officers, Amompharetus by name.[4] This man conceived that the movement ordered by Pausanias was a retreat, and so forbidden by the strict code of Spartan military honour. Accordingly he refused to move. An angry dispute followed, Pausanias and his second in command doing all they could to convince their subordinate, he obstinately adhering to his decision. In the midst of the argument a messenger from the Athenians arrived on horseback. They were perplexed by the inaction of the Spartans, and, very possibly, suspicious of some design which would be compromising to their own safety. At the moment of this messenger's arrival Amompharetus had delivered his ultimatum. Taking up from the ground a huge stone, he cast it at the feet of Pausanias, saying at the same time, "I give my vote for staying"—the same word serves in Greek for vote and pebble, pebbles being used in the ballot-boxes. Pausanias hurriedly explained the situation to the Athenian, and begged him to carry back a message that he hoped his countrymen would not move till he could overcome the difficulty in which he found himself. This, indeed, seemed almost hopeless. At last, just before dawn, Pausanias made up his mind to leave the refractory captain behind. Finding himself alone with his company, he would, he hoped, consent to follow. And this was what actually took place.
By this time day was dawning, and Mardonius became aware of what had happened. He seems to have looked upon the movement in much the same way as Amompharetus had done. It was a flight. These Spartans, for all their boasted courage, were running away. His Persian troops answered the command by a disorderly advance. They crossed the Asopus, which, it will be remembered, flowed in front of their position, and hurried in the track of the Spartans; the rest of the Asiatics followed their example. Pausanias sent a message to the Athenians, telling them that the Persians were concentrating their whole strength against his division, and begging that they would come to his help, at least by sending their archers. The Athenians, however, had by this time work enough of their own to deal with, for the Thebans and Thessalians had commenced an attack upon them.
The Spartans, therefore, had to bear the brunt of the Persian attack alone. They had ten thousand heavy-armed and four times as many light-armed, numbers slightly increased by the contingent from Tegea, a force of three thousand, equally divided between the two classes of troops. Pausanias, who seems to have shown little ability or presence of mind from the beginning to the end of the campaign, was busy with the customary sacrifice. Unfortunately the victims showed no encouraging signs, and he was content, possibly was compelled by the public opinion of his men—for a Greek army, even when it came from Sparta, was a democracy—to postpone any movement of offence till the Fates seemed propitious. Meanwhile his men were falling about him—one of the slain was reputed to be the handsomest man in the whole Greek army.[5] In an agony of distress, Pausanias lifted his eyes to the Temple of Heré, which stood on a conspicuous height, and prayed for the help of the goddess. The signs immediately changed, and the welcome signal to charge was given. The Tegeans seem to have already moved. Together they advanced against the Persian line, which was protected by a rampart of wicker shields, from behind which the archers had been pouring volleys of arrows. The rampart was soon broken down. Then a fierce hand-to-hand fight began. Again and again the Persian braves dashed themselves on the Spartans' spears and broke or strived to break them. "They were not one whit inferior to the Greeks in boldness and warlike spirit"—such is the testimony which men who had borne their part in that fierce struggle bore to the bravery of their antagonists—but their armament was less effective and their military training less complete. The battle raged most furiously about the person of Mardonius, who was surrounded by a bodyguard of a thousand Immortals. As long as he lived these picked warriors held their own; when he was struck down—a Spartan, Aeimnestus[6] by name, had the credit of the deed—they fled in wild confusion to their camp. A body of forty thousand was led off the field by the general in command, when he saw how the fortune of the day was going.
On the right wing of the Persian army the Theban infantry, always distinguished for its steady courage, held its own for a considerable time against the Athenians. It stood alone, however. The other Greeks, whom Xerxes or his lieutenant had pressed into the Persian service, felt no zeal for the cause, and took the first opportunity that occurred of retreating. The Thebans, who must have been much inferior in numbers to their Athenian adversaries, were driven back, with a considerable loss in killed. They took refuge within the walls of their city. Their cavalry, indeed, achieved the only success that the army of Mardonius could boast. News reached the Greek centre, in its position outside Platæa, that the right wing had put the Persians to flight, and it hurriedly advanced to take a share in the victory. The movement was made in a careless and disorderly way. So relaxed was discipline that the whole force did not even keep together. Two of the contingents, from Megara and Phlius (a small state in the north of the Peloponnese) were attacked by the Theban cavalry as they crossed the plain and suffered a very heavy loss, as many as six hundred being slain. "So they perished without honour," says Herodotus. It must be owned that from first to last the smaller Greek States earned little distinction in the war.