Darius and his host advanced along the coast of what is now Bulgaria, but which was then called Thrace. They crossed the Danube, and prepared to give battle to the Scythian army and take the cities of the Scythians.
But the Scythians had no cities, and they evaded a battle, and the war degenerated into a tedious and hopeless pursuit of more mobile enemies. Wells were stopped up and pastures destroyed by the nomads. The Scythian horsemen hung upon the skirts of the great army, which consisted mostly of foot soldiers, picking off stragglers and preventing foraging; and they did their best to persuade the Ionian Greeks, who had made and were guarding the bridge across the Danube, to break up the bridge, and so ensure the destruction of Darius. So long as Darius continued to advance, however, the loyalty of his Greek allies remained unshaken.
But privation, fatigue, and sickness hindered and crippled the Persian army; Darius lost many stragglers and consumed his supplies, and at last the melancholy conviction dawned upon him that a retreat across the Danube was necessary to save him from complete exhaustion and defeat.
In order to get a start in his retreat he sacrificed his sick and wounded. He had these men informed that he was about to attack the Scythians at nightfall, and under this pretence stole out of the camp with the pick of his troops and made off southward, leaving the camp fires burning and the usual noises and movements of the camp behind him. Next day the men left in the camp realized the trick their monarch had played upon them, and surrendered themselves to the mercy of the Scythians; but Darius had got his start, and was able to reach the bridge of boats before his pursuers came upon him. They were more mobile than his troops, but they missed their quarry in the darkness. At the river the retreating Persians "were brought to an extremity of fear," for they found the bridge partially broken down and its northern end destroyed.
At this point a voice echoes down the centuries to us. We see a group of dismayed Persians standing about the Great King upon the bank of the streaming river; we see the masses of halted troops, hungry and warworn; a trail of battered transport stretches away towards the horizon, upon which at any time the advance guards
