The mighty Persian army marched to the Hellespont. A marble throne was built for Xerxes on a hilltop, and there he sat gazing at the hundreds of thousands of men encamped below him. Suddenly he began to weep, because the thought had struck him that a hundred years from then not one of those men would be alive. This was undoubtedly true, but no able commander would have had time to think of it on the eve of an invasion.

On the following day came the crossing of the bridges, and the most superb procession that the world has ever seen. There was Xerxes himself in a magnificent war-chariot, and there was the even more magnificent chariot of the sun-god with its eight white horses. There were the Ten Thousand Immortals, the special guard of the king, who marched gravely and steadily with crowns on their heads. There were troops from the many nations subject to Xerxes. Some of them wore coats of mail, some wore linen corselets, and some wore long cloaks. They carried all sorts of weapons; spears, daggers, bows, and arrows, and even heavy clubs knotted with iron, according to the customs of their countries. There were long lines of camels and servants with provisions. There were also more than four thousand ships gathered together in the waters. Fortunately for all folk who like to hear a good story, there was a little four-year old boy then living in Asia Minor named He-rod'o-tus. When he grew up, he traveled to many places where interesting things had happened, learned all that he could about them, and wrote what he had learned. It is he who tells us about the expeditions of the Persians and this crossing of the bridges of boats by the greatest army that was ever brought together.

The Greeks were in so great anxiety that some of them were ready to send earth and water at once. Others were determined to resist even the mighty Persian sovereign. But they were so jealous of one another that even in their trouble they quarreled about the leadership. At length Athens, Sparta, and a few other states agreed to stand together, and the command was given to Le-on'i-das, the Spartan king.

The Persians were marching nearer and nearer, keeping close to the shore. Xerxes heard that a few of the Greeks were at the Pass of Ther-mop'y-lę, but with his hundreds of thousands of men that was a small matter, and he marched on. He had just lost four hundred ships in a storm, and the Greeks were guarding the Eu-ri'pus, the strait between the island of Eu-bœ'a and the mainland, or else he might have carried his men to Attica by water — if he had thought it was worth while.

At Thermopylę the mountains jut out into the sea and leave only a narrow passage between them and the water. Here Leonidas with three hundred Spartans and about six thousand men from other tribes took their stand against the enormous numbers of the Persians. There were two days of terrible fighting. Then a traitor, who hoped for a great reward, told Xerxes that there was a footpath by which his men could go over the mountains and around the Pass.

When Leonidas found that the path had been discovered, he knew that he could not hold Thermopylę. Nevertheless, he would not withdraw. "The laws of our country forbid that we should leave the place that we have been sent to guard," he said. The others made their way to their homes; but the Spartans and also the Thes'pi-ans refused to retreat. The Persians came upon them from above and from below. They fought with their weapons, then with their teeth, with their fists, with stones, with anything that would make a wound or strike a blow, until every man of them was slain. The Persians had won the Pass of Thermopylę, and they set out for Athens.

There was now no reason for guarding the Euripus, and the Greek warships sailed through it toward the south. The commander of the Athenian vessels was The-mis'to-cles, a man who had fought at Marathon. He was a far-seeing man, and at the time when the Greeks were rejoicing because they had driven away Darius, he was serious and grave. "The Persians will come again," he declared, "and we must learn to defend ourselves on the water as well as on the land." His constant cry was, "Build ships, build ships." The Athenians were slow to yield, but finally a fleet was built. This was the fleet which Themistocles was bringing down the Euripus. This commander never overlooked any chances. He knew that there must be Ionians, who were of Greek descent, in the army of Xerxes, and he cut messages for them on the rocks along the way. "Men of Ionia," these inscriptions said, "come over to our side if possible; if you cannot do this, we pray you stand aloof from the contest, or at least fight backwardly."

The Persians were aiming first at Athens; and the other kingdoms had abandoned her to her fate. The states lying to the south of the Isthmus of Cor'inth, the Pel-o-pon-ne'sus, as that part of the country was called, were working night and day to build a high wall across the Isthmus to protect themselves and their own cities; and the Persians swept down upon Athens. They plundered and burned and destroyed till there was hardly one stone left standing upon another. The people of the city were saved; for just before the coming of the Persians they had been crowded into boats and carried to safe places.

Long before this, the Athenians had sent to the oracle at Delphi for advice. One line of it was, "Holy Salamis, thou shalt destroy the offspring of women." but who could say whether the "offspring of women" meant Greeks or Persians? Themistocles believed that it meant the Persians, and that a naval victory at Salamis was the only hope of the Greeks.

The men of the Peloponnesus who were building the wall objected. "We will fight at the Isthmus," they said, "and then if we are defeated, we can retreat to our homes; but we will not go out to fight on the water." Themistocles believed that the oracle had promised a victory at Salamis and nowhere else, and he resolved to make the objectors fight, whether they would or not. He sent a faithful slave to Xerxes to say that the Greeks were divided, that some were for him and some were against him. "Now is your chance to win a glorious victory," the message ended. The Persians were made to think that this message was sent by some Greek commander who favored their side. The envoys of the states met again and talked far into the night. While they debated, a message was brought to Themistocles: "There is one without who would speak to you." It was an Athenian named Ar-is-ti'des. He, too, had been at Marathon. He was so upright and honorable that he was known as "the Just." He had believed that Themistocles was entirely in the wrong in urging the building of ships. He had opposed the course of his rival so strongly that at length the matter was brought to the test of ostracism. This was a peculiar custom of the Athenians. If it was thought that any one man was gaining too much power, the citizens were called together, and each was requested to write on a shell (os'tra-kon) the name of any one who he thought might endanger the liberty of the state. If any one person received six thousand votes, he was banished for ten years. It was in this way that Aristides had been banished. The Greeks had permitted all those to return who had been sent away, lest they should join the Persians; and here was Aristides in the darkness of the night, bringing a message to his old opponent Themistocles.

Aristides was so earnest a patriot that he was perfectly willing to help even Themistocles to win glory if by so doing he could save his country, and he whispered, "The Persian ships are at the entrance of the strait." Then Themistocles was delighted. He saw that his trick had deceived the enemy and that now the Greeks would have to fight on the water.

So it was that the battle of Salamis came about. The Greek ships formed in a line extending from Attica to Salamis. The Persian vessels lay to the south of them. Then the conflict began. All day long the battle raged. Both sides fought with the utmost courage. Indeed, the Persians would have done better if their commanders had not been quite so fearless. Every one of them was eager to do some brave deed under the eye of the king, have his name set down by the royal secretaries as one of the king's "benefactors," and win the reward and honors that would await him. The result of this was that when the foremost Persian ships were put to flight, the vessels coming up behind them pressed on so zealously that they knocked against them and against one another. Rudders were destroyed, oars were snapped off, and the ships of the invaders drifted about helplessly, were rammed by the Greeks, and sank by the score. The Greeks were here, there, and everywhere; and wherever a Grecian vessel went, it ran its sharp prow into the sides of the Persian ships. The Greeks even sailed around the Persian fleet and attacked it from the rear. When night came, they had won the victory. Xerxes started for home, sailing as fast as a ship would carry him for he was terribly alarmed lest the Greeks should destroy the bridges over the Hellespont before his troops could march across them. Herodotus says that if all the men and women in the world had advised him to stay, he would not have done it. One of his generals was eager to try again, and he remained with three hundred thousand men. By this time the states had learned that they must unite. There was a savage battle at Pla-tę'a. The Greeks were victorious, and this ended the attempt of the great king of Persia to overpower the little country of Greece.

Xerxes prepares to invade Greece. — The crossing of the Hellespont. — Herodotus. — Leonidas commands the Greek forces. — Thermopylę. — The inscription on the rocks. — The destruction of Athens. — The advice of the oracle. — Themistocles tricks the Persians. — Ostracism. — The battle of Salamis.