King Nebuchadnezzar, of whose acts the book of Daniel is so full, had restored the kingdom of Babylon, beyond the Euphrates. He had made the city of Babylon, the greatest city in the world. Stray Greeks had visited it and brought back stories of the amazing palaces and temples, the hanging gardens and terraced parks. With the death of King Nebuchadnezzar the kingdom of Persia rose to fame under King Cyrus.

Now the deeds of Nebuchadnezzar had not troubled Greece at all, but now that Cyrus was King of Persia, things were different. Already Babylon had fallen to him, and he was casting his eyes towards the Greek colonies, on the shores of Asia Minor under one Crœsus.

A story is told of these two monarchs. Cyrus had determined to put Crœsus to death; so he built a great pyre, and placed Crœsus on it, bound in chains. While he stood waiting for the flames to rise around him, some words uttered by Solon, came into his head, and groaning aloud he cried, "Oh, Solon, Solon, Solon!"

Cyrus heard him, and asked of whom he spoke. Crœsus quoted Solon's wise words, "Call no man happy, till his death."

Cyrus was greatly struck. "Surely," he reflected, "here is a man worth saving." And he ordered the prisoner to be set free. But already, the flames were blazing with such strength and fury, that the men could not put them out. Then Crœsus cried to one of the Greek gods for help, and the story says, suddenly clouds came into the clear sky and a downpour of rain put out the roaring fire. So Crœsus lived and became the friend and adviser of the King of Persia.

Under Cambyses, the son of Cyrus, Persia became yet more powerful, for he conquered Egypt from the Pharaohs, and, as we have already seen, would have taken Carthage, if the Phœnician sailors had helped him.

But it was the third great King of Persia, Darius, that the Greeks feared the most, and they had good reason to fear; for was he not king of the mightiest kingdom of the East?

Had not the Persians already subdued the sea-coast on the farther shores of the Archipelago? was not the land of Egypt—that rich and fertile land—theirs too? Was it likely that Darius would be content with what he had, when he could command the soldiers of so many lands?

No sooner had he set his kingdom in order at home, than he started forth on his conquests.

Now when Darius made up his mind to go into Europe, his shortest way would have been to cross the Black Sea; but this was impossible in early days. To get to Europe at all, the water must be crossed, so Darius ordered the Ionian Greeks living on the coast and in the islands off the coast, to raise a fleet of six hundred ships. Then he marched to the shores of the Bosphorus, a narrow strait that divides Asia from Europe. Here a bridge of boats had been made by an engineer from one of the Greek islands belonging to Persia, and the Persian army marched over it to the shores of Europe.

Darius marched the army northward till he reached the river Danube, which, at this time, was supposed to be the greatest river in the world. Here, according to their orders, the Greeks had already built a bridge of boats, across the river. Darius now took a cord—so says the old legend—in which he tied sixty knots.

"Untie one of these knots every day," he said to the Greek captains, "and remain here and guard the bridge till they are all untied. If I have not returned at the end of that time, sail home."

The sixty days passed, the knots were untied, but Darius did not return. The Greeks heard rumours, that the Persians had been defeated and were in full retreat, and that their only hope of safety lay in the bridge.

"Let us destroy the bridge," urged one of the Greeks, Miltiades, the future hero of Marathon; "then shall Darius and his army perish and we shall regain our freedom."

"No," said another; "by destroying Darius, we destroy ourselves."

His counsel prevailed. The Greeks kept the bridge, and Darius passed back in safety.