The only narrative about Oroetus can be found in the third book of the Histories by the Greek researcher Herodotus (c.480-c.429). Actually, he has two stories to tell. In the first story, he deals with the execution of Polycrates, the tyrant of the Greek island Samos; in the second story, Herodotus describes the fall of Oroetus.
According to Herodotus,
Polycrates was the first Greek we know of to plan the dominion of the sea [...] and he had high hopes of making himself master of Ionia and the islands.note[Herodotus, Histories 3.122.]
He was successful and he was so blessed by the gods that even when he threw a precious ring into the sea, a fisherman would catch the fish that had swallowed the ring. However, the Egyptian pharaoh Amasis, who was allied with Polycrates, understood that a man who was so lucky would one day be punished by the gods, who are envious of human happiness. And this was, to him, sufficient reason to end the alliance.
Amasis had a prophet's eye. About the time of the death of the Persian king Cambyses, in July 522 BCE, Polycrates was invited by the satrap of Lydia, Oroetus, to come to Sardes. Herodotus quotes the message:
I understand, Polycrates, that you have an important enterprise in mind, but your resources are not equal to your designs. I have a proposal to make which, if you adopt it, will ensure your success - and my own safety, for it is clear from reports I have received that Cambyses is plotting my death. Come, then, and get me out of the country; I promise you a share in everything I possess, and that will give you enough money to get control of the whole of Greece. If you have any doubts about my wealth, send whoever it is you must trust, and I will show him what I have.note[Herodotus, Histories 3.122; tr. Aubrey de Selincourt.]
Polycrates, who was, in Herodotus' words, "very fond of money", prepared to visit Oroetus, and ignored the warnings of a soothsayer and his daughter, who had dreamt that her father was washed by the god Zeus and anointed by the Sun.
Somehow or other - the precise manner need not be told - Oroetus had him murdered, and the dead body hung on a cross. [...] The dream of Polycrates' daughter was thus fulfilled by his crucifixion: when rain fell, he was washed by Zeus, and he was anointed by the Sun when under the sun's heat the moisture was sweated out from his body. This, then, was the end of the long-continued prosperity of Polycrates: it was just as Amasis, king of Egypt, had previously foretold.note[Herodotus, Histories 3.125; tr. Aubrey de Selincourt.]
In Herodotus' view, the story of Polycrates summarizes the human condition; the words of Amasis that the gods are envious of human happiness and punish human beings who are too happy, express his own opinion. The real story may have been different.
Polycrates of Samos had built a very large navy, which was paid for by the Egyptian pharaoh, who must have seen Polycrates as a useful ally in the struggle against Persia. (The Egyptians hired their mercenaries in Caria, which is not far from Samos.) In 525 BCE, however, Egypt was conquered by the Persian king Cambyses and Polycrates' source of money dried up. At this moment, Oroetus offered the very thing the Samian ruler needed: gold and silver.
Oroetus' real motive is unknown. It may be that he simply did what he was expected to do during the war between Persia and Egypt: attacking an Egyptian ally. The execution of Polycrates may have been ordered by Cambyses himself. An alternative explanation is that Oroetus had fallen into disgrace with his king, and decided to do something to regain the king's favor.
Oroetus had to pay for this murder. After the death of Cambyses, and througout the period when Persia was controlled by the false Smerdis, he had lived in Sardes and offered no help to his countrymen in resisting the Median usurpation. He had, morover, during these unsettled times, procured the death of Mitrobates, the governor of Dascyleium [...], and also of Mitrobates' son Cranaspes, a man hardly less distinghuished than his father. Nor were these two murders by any means his only acts of violence; he also, for instance, made away with one of Darius' courtiers; the man had come with a message which was not to Oroetus' taste, so he sent a party to waylay him on his return journey. He was killed, and neither his body, nor that of his horse, were ever discovered.note[Herodotus, Histories 3.126; tr. Aubrey de Selincourt.]
Herodotus describes Oroetus as a criminal, but this may be a bit too simple. In March 522, a Magian named Gaumâta had seized power in the Achaemenid empire, claiming to be Smerdis, the brother of the legitimate king Cambyses. (Gaumâta could do this, because the real Smerdis had been killed secretly.) Cambyses had advanced to the usurper, but had died before he had reached Persia; the false Smerdis was able to rule for several months. However, Cambyses' relative Darius had killed the usurper (29 September 522). Darius had become king and had faced a serious crisis: nearly all provinces of the Achaemenid empire revolted. The most important rebellion was that of the Medes, whose leader was king Phraortes. His rebellion spread to the east to Parthia and to the north to Armenia. It took exactly one year and nineteen battles to pacify the Achaemenid empire again.
Probably, Oroetus had refused to send troops to supprt Darius. Or maybe, Oroetus was one of the rebels, although Darius does not mention him in the Behistun inscription, in which he describes the events of the year 522-521 and mentions several rebel kings.The execution of Mitrobates, the satrap of Dascyleium, and Darius' messenger fit this picture.
Darius, once his power was established, was anxious to punish Oroetus for his many crimes, and not least for the murder of Mitrobates and his son. He thought it would be unwise, things being as they were, to send an armed force openly against him; for the country was still in an unsettled state; he himself had only recently come to the throne, and he knew that Oroetus was a powerful man, being governor of Phrygia, Lydia and Ionia, with a thousand Persians in his bodyguard. Darius had recourse, in consequence, to subtler methods. [....]
Bagaeus, the son of Artontes, at once set about having a number of documents prepared on various subjects, which he sealed with the king's seal, and took with him to Sardes. Here he called upon Oroetus, and in his presence opened the papers one by one, handling them to the king's secretary (an officer who forms part of every governor's establishment), with instructions to read them aloud. His object in this was to test the loyalty of Oroetus' bodyguard in case they might be willing to act against their master.
When, therefore he noticed that they regarded the documents with respect - and, still more, the words they heard read from them - he passed one to the secretary which contained an order, purporting to come from Darius, to the effect that the guards were to refuse service to Oroetus. The order was read out, and the guards promptly laid their spears at Bagaeus' feet. Then Bagaeus, seeing the written order obeyed, ventured to hand the secretary the paper he had reservered till last. It contained the words: "King Darius commands the Persians in Sardes to kill Oroetus." The guards immediately drew their scimitars, and despatched him. And that was how Oroetus the Persian was punished for his betrayal of Polycrates.note[Herodotus, Histories 3.127-128; tr. Aubrey de Selincourt.]
The last line tells us a lot about Herodotus' ideas about crime and punishment, but it is unlikely that Darius cared much about Polycrates, who had, after all, been an ally of an enemy of the Achaemenid empire. What counted was that Oroetus had not shown sufficient signs of loyalty and had murdered a satrap who had probably supported Darius. The members of Oroetus' bodyguard, who must have heard the stories about the suppression of the rebellions, must have been happy that they were not forced to fight for their commander.
It may be noted that the words of Bagaeus' last letter, "King Darius commands the Persians in Sardes to kill Oroetus", are remarkably similar to other texts from the Achaemenid empire. It is possible that the real message was: "King Darius says: The Persians in Sardes must kill Oroetus."
Bagaeus may have been Oroetus' successor as satrap; the next satrap was Otanes, who added Samos to the Achaemenid empire.