The Histories · 8.75

Then Themistocles, when his opinion was like to be defeated by the Peloponnesians, secretly went forth from the assembly, and having gone out he sent a man to the encampment of the Medes in a boat, charging him with that which he must say: this man's name was Sikinnos, and he was a servant of Themistocles and tutor to his children; and after these events Themistocles entered him as a Thespian citizen, when the Thespians were admitting new citizens, and made him a wealthy man. He at this time came with a boat and said to the commanders of the Barbarians these words: "The commander of the Athenians sent me privately without the knowledge of the other Hellenes (for, as it chances, he is disposed to the cause of the king, and desires rather that your side should gain the victory than that of the Hellenes), to inform you that the Hellenes are planning to take flight, having been struck with…

Herodotus of Halicarnassus · trans. G. C. Macaulay, 1890
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