(Ἱστιαῖος), tyrant of Miletus, commanded his contingent of Ionians in the service of Dareius in the invasion of Scythia by the Persians (B. C. 513), when he was left with his countrymen to guard the bridge of boats by which the army had crossed the Danube. Sixty days had been assigned by the Persian king as the period of his absence, marked by as many knots tied in a rope, one of which was to be untied daily. When the time had passed, and the Persians did not appear, being still engaged in a vain pursuit of the Scythians, the Ionians took counsel about their return. The proposal of Miltiades, the Athenian, to destroy the bridge, and leave the Persians to their fate, would have occasioned the certain destruction of Dareius and his army, had not Histiaeus persuaded his countrymen, the rulers of the Greek cities on the Hellespont and in Ionia, not to take a step which would lead to their own ruin, depending as they did upon the Persians for support against the democratic parties in their respective cities. Deceiving the Scythians by professing to fall in with their wishes, and to be anxious for the destruction of Dareius, the wily Greek persuaded them to depart in search of him, making a show of destroying the bridge by removing the part of it next Scythia. When the Persians, retreating from their unsuccessful march, returned to the Danube, where they happened to arrive after nightfall, they were naturally alarmed lest the Greeks should have deserted them, until an Egyptian, noted in the army for his loud voice, was ordered to shout out the name of Histiaeus of Miletus, who, hearing the call, made all speed to transport them to the safe side of the river.

Dareius never forgot this signal service. On his return to Sardis Histiaeus was rewarded with the rule of Mytilene. Histiaeus, already in possession of Miletus, asked and obtained a district on the Strymon, in Thrace, where, leaving Miletus under the charge of his kinsman, Aristagoras, he built a town called Myrcinus. apparently with a view of establishing an independent kingdom. The spot was well chosen, as the neighbouring country was rich in tin ore and silver mines: but he was not allowed to carry his designs into execution. Megabazus, a Persian officer, whom Dareius had left in Europe to complete the conquest of Thrace, advised the king to recal his promise, and not to allow an able and crafty man, like Histiaeus, to raise a formidable power within the empire. Histiaeus followed Dareius reluctantly to Susa, where he was detained for thirteen years, till the outbreak of the Ionian revolt, kindly treated, but prohibited from returning.

On the news of the burning of Sardis by the Athenians (B. C. 499) [ARISTAGORAS], whom Aristagoras had induced to send help to their kinsmen of Ionia, Dareius charged Histiaeus with being a party to the revolt. His suspicions were correct: Histiaeus had encouraged Aristagoras in his design, employing a singular expedient to escape detection. He had shaved the head of one of his slaves, branded his message on the skin, and sent him to Aristagoras, after the hair had grown, with the direction to shave it off again. A revolution in Ionia might lead, he hoped, to his release : and his design succeeded. It is unaccountable that Dareius should have been so easily deceived : yet he suffered Histiaeus to depart, on his engaging to reduce Ionia, and to make Sardinia, which he described as an important island, tributary to the Persians.

On his arrival at Sardis he found that the revolt had not succeeded: the Athenians had declined to send fresh succour, and the Ionian cities were being reduced again. Artaphernes, satrap of Sardis, showed himself less credulous than Dareius: " It was you that stitched the shoe," he said to Histiaeus, " which Aristagoras did but wear." Histiaeus, in alarm, had recourse to the Chians, whom he with difficulty persuaded to receive him: then, imposing upon the Ionians, who regarded him with distrust, by a crafty story that Dareius meant to remove them to Phoenicia, after the fashion of Eastern conquerors, he began to intrigue with some Persians in Sardis, who were willing to listen to his proposals. Artaphernes discovered the plot, and put the Persians to death : upon which Histiaeus, after in vain trying to persuade the inhabitants of Miletus to receive him back again, succeeded at length in raising a small force in Lesbos, with which he proceeded to Byzantium, still in revolt, and seized all vessels sailing from the Euxine that refused to acknowledge him as their master. On the reduction of Miletus (B. C. 494), the most important step in the second conquest of Ionia, Histiaeus made a bold attempt to establish himself in the islands of the Aegean, and actually succeeded in taking possession of Chios after some resistance, the inhabitants having lost nearly all their forces at the battle of Lade. Thasos might have fallen under him also, when the news that the Phoenician fleet, having assisted in conquering Miletus, was sailing northwards to complete the conquest of Ionia and Aeolis, induced him to return to Lesbos. Hence he made a descent on the opposite coast, to ravage the plain of the Caicus and Atarnea, but was defeated and taken prisoner by a troop of Persian cavalry under Harpagus. He would have been slain in the pursuit had he not called out in Persian that he was Histiaeus of Miletus, hoping that his life would be spared. If he had fallen into Dareius's hands, it would have been so : but Harpagus and Artaphernes caused him to be put to death by impalement, and sent his head to the king. Dareius received it with sorrow, and buried it honourably, blaming the haste of his officers : no injury could make him forget that he had once owed to Histiaeus his army, his kingdom, and his life. The adventurous history of Histiaeus does not show any signs of his having possessed great or noble qualities of mind. Attachment to his country is the only pleasing trait in his character; and even this is mixed up with motives of a lower kind. Personal ambition is the only reason given for his saving the army of Dareius; and afterwards it was selfish motives, not true patriotism, that led both Aristagoras and himself to bring down the vengeance of the Persians upon his country. In policy and dissimulation he was undoubtedly well skilled, and not deficient in daring. The attachment of Dareius to him is more striking than any qualities in his own character. (Hdt. 4.137, 138, 141, 5.11, 23, 24, 30, 35, 105-107, 6.1_5, 26_30; Polyaen. 1.24; Tzetz. Chil. 3.512. 9.228; Gel. 17.9.)