Otanes (Old Persian Utâna): Persian nobleman, one of the seven conspirators who killed the Magian usurper Gaumâta and helped Darius I the Great become king (29 September 522 BCE). Several years later, he added the Greek island Samos to the Achaemenid Empire.
In March 522, a Magian named Gaumâta seized power in the Achaemenid Empire, claiming to be the brother of the legitimate king Cambyses, Smerdis. Gaumâta could do this, because Smerdis had been killed secretly. Immediately, Cambyses advanced to the usurper, but he died before he reached Persia; the false Smerdis was able to rule for several months. This is known from two sources, the Behistun inscription and the Histories by the Greek researcher Herodotus.
According to Herodotus, Otanes, the brother of Cassandanenote[Herodotus, Histories 3.68, 3.88.] (wife of Cyrus, nother of Cambyses and the real Smerdis), was the first to become suspicious of the false Smerdis.note[Herodotus, Histories 3.68-69.] From his daughter Phaedymia, who was married to the king, he learned that Smerdis was in reality a Magian. On hearing this news, Otanes invited Aspathines and Gobryas to discuss the situation.note[Herodotus, Histories 3.70-71, 3.76.] Together, they decided to invite three other conspirators: Hydarnes, Intaphrenes and Megabyzus. They were still making plans, when Darius arrived and sided with them. He convinced the seven to strike immediately and not to wait, as Otanes had proposed. On 29 September 522 BCE, the seven killed the false Smerdis.
That Otanes was involved in the killing of Gaumâta is confirmed by the Behistun inscription. This inscription also tells us that the name of Otanes' father, which was Thukhra. Herodotus is mistaken when he calls him Pharnaspes,note[Herodotus, Histories 3.68.] but is is possible to save him by accepting the hypothesis that Thukra was a nickname ("redhead").
Herodotus tells us that after the murder, the seven men discussed the future constitution of Persia.note[Herodotus, Histories 3.80-81, 6.43.] Otanes said that Persia ought to be a democracy; Megabyzus argued for an oligarchy and Darius said that monarchy was the best kind of rule. The other four noblemen sided with him, and Darius became king. Herodotus stresses that this discussion really took place. Probably, he has misunderstood a debate about the future of Persia: was it to be a centralized monarchy (which it became) or was it to be a loosely organized federation (as it had been)?
When it was decided that Persia was to be a monarchy and Darius was to be its king, Otanes opted out of it and received special rights:
To this day, the family of Otanes continues to be the only free family in Persia, and submits to the king only so far as the members of it may choose. They are bound, however, to observe the law like anyone else.note[Herodotus, Histories 3.83.]
That is, at least, Herodotus' story. But there may be more than meets the eye: perhaps Otanes was a rival candidate to the Persian throne. There are many elements in Herodotus' story that point into this direction. In the first place, we see that Otanes started the conspiracy and that Darius sided with them later. In the second place, Otanes and Darius argued for opposite ideas on two occasions: should the seven wait or strike immediately and should Persia be a democracy or a monarchy? In the third place, Otanes had a powerful claim to the throne because he was the brother of Cassandane, the queen of king Cyrus the Great, and the father of Phaedymia, the queen of Cambyses and the false Smerdis. (Darius' claim to the throne was based on the fact that he belonged to a younger branch of the family of Cyrus and Cambyses, the Achaemenids.)
It is likely that Otanes, who, according to Herodotus, decided to stay aloof from Persian politics, prepared the road for Darius to become king. It was necessary: after the assassination of Gaumâta, the Babylonians had revolted and the crisis was acute. Otanes stepped aside and Darius honored him by marrying his daughter Phaedymia, who had already been married to Cambyses and the false Smerdis. When Darius married her, his rule became more legitimate. At the same time, Otanes married a sister of Darius. They probably were the parents of Amestris, who was to marry king Xerxes.
That the king trusted Otanes, is also suggested by the fact that he ordered his father-in-law, who was probably serving as satrap of Lydia, to conquer the Greek island Samos (c.517 BCE).note[Herodotus, Histories 3.141-149.] This island had been without strong leader since an earlier Lydian satrap, Oroetus, had executed Polycrates of Samos. Its new, pro-Persian ruler, was to be a man named Syloson. Herodotus tells us:
As for Samos, the Persians took the entire population like fish in a drag-net, and presented Syloson with an empty island. Some years later, however, Otanes contracted some sort of disease of the genital organs and that, in conjunction with a dream he had, induced him to repopulate the place.note[Herodotus, Histories 3.149; tr. Aubrey de Selincourt.]
This is the last piece of information about Otanes. In 513 BCE, a new satrap was appointed in Lydia, Artaphernes. Probably, Otanes had died.
Otanes had a son Patiramphes, who served as the driver of the chariot of king Xerxes during his campaign to Greece. As we have already seen above, Otanes was probably also the father of Xerxes' first wife, queen Amestris.