Plutarch, Themistocles
Bernadotte Perrin, Ed.

Now Thucydides¹ and Charon of Lampsacus relate that Xerxes was dead, and that it was his son Artaxerxes with whom Themistocles had his interview; but Ephorus and Dinon and Clitarchus and Heracleides and yet more besides have it that it was Xerxes to whom he came. With the chronological data Thucydides seems to me more in accord, although these are by no means securely established. [2] Be that as it may, Themistocles, thus at the threshold of the dreadful ordeal, had audience first with Artabanus the Chiliarch, or Grand Vizier, and said that he was a Hellene, and that he desired to have an audience with the King on matters which were of the highest importance and for which the monarch entertained the most lively concern. Whereupon the Chiliarch replied: ‘O Stranger, men's customs differ; different people honor different practices; but all honor the exaltation and maintenance of their own peculiar ways. [3] Now you Hellenes are said to admire liberty and equality above all things; but in our eyes, among many fair customs, this is the fairest of all, to honor the King, and to pay obeisance to him as the image of that god who is the preserver of all things. If, then, thou approvest our practice and wilt pay obeisance, it is in thy power to behold and address the King; but if thou art otherwise minded, it will be needful for thee to employ messengers to him in thy stead, for it is not a custom of this country that the King give ear to a man who has not paid him obeisance.’ [4] When Themistocles heard this, he said to him: ‘Nay, but I am come, Artabanus, to augment the King's fame and power, and I will not only myself observe your customs, since such is the pleasure of the god who exalts the Persians, but I will induce more men than do so now to pay obeisance to the King. Therefore let this matter by no means stand in the way of the words I wish to speak to him.’ [5] ‘And what Hellene,’ said Artabanus, ‘shall I say thou art who hast thus come? Verily, thou dost not seem to be a man of ordinary understanding.’ And Themistocles said: ‘This, Artabanus, no one may learn before the King.’

So indeed Phanias says, and Eratosthenes, in his book ‘On Wealth,’ adds the statement that it was through a woman of Eretria, whom the Chiliarch had to wife, that Themistocles obtained interview and conference with him.