The Histories · 8.113

Xerxes meanwhile with his army stayed for a few days after the sea-fight, and then they all began to march forth towards Boeotia by the same way by which they had come: for Mardonios thought both that it was well for him to escort the king on his way, and also that it was now too late in the year to carry on the war; it was better, he thought, to winter in Thessaly and then at the beginning of spring to attempt the Peloponnese. When he came to Thessaly, then Mardonios chose out for himself first all those Persians who are called "Immortals," except only their commander Hydarnes (for Hydarnes said that he would not be left behind by the king), and after them of the other Persians those who wore cuirasses, and the body of a thousand horse: also the Medes, Sacans, Bactrians and Indians, foot and horsemen both. These nations he chose in the mass, but from the other allies he selected by few…

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