John Gill's Exposition of the Whole Bible
2 Chronicles 36:20
And them that had escaped from the sword carried he away captive,.... The king of Babylon, or his general by his orders, excepting some poor persons left to till the land, see Jeremiah 52:15,
where they were servants to him and his sons; his son Evilmerodach, and his grandson Belshazzar, Jeremiah 27:7:
until the reign of the kingdom of Persia; until that monarchy began, as it did upon the taking of Babylon by Cyrus king of Persia. This is the first place we meet with this name of Persia in Scripture. The Arabic writers differ about the origin of it; some derive it from Pars the son of Arsham (Arphaxad), the son of Shem; others from Pars the son of Amur, the son of Japheth; and others say Pars was the son of Elam, the son of Shem, the son of Noah a; but Bochart b, seems to be most correct in the derivation of the word, who observes, from Xenophon c, horses were very rare in this country; and very few could ride them before the times of Cyrus, who taught his foot soldiers to ride horses; and hence it became common, so that none of the best men of the land cared to be seen on foot; yea, he made a law, that it should be reckoned infamous if any of those he had taught the art of riding were seen to go on foot, though ever so little a way; from this sudden change made in his time the people were called Persians, and the country Persia; in the Arabic language, "pharas" signifying a horse, and "pharis" a horseman; and the same writer observes, that hence it is that no mention is made of this country, in the name of Persia, by Isaiah and Jeremiah; but by Ezekiel and Daniel, who were contemporary with Cyrus; and in this book and the following historical ones, which were wrote after the Babylonish captivity, as their history shows; and that this book was, is clear from the preceding clause, as well as from the three last verses.
a Hyde, Hist. Relig. Vet. Pers. c. 35. p. 418, 419. b Phaleg. l. 4. c. 10. col. 224. c Cyropaedia, l. 1. c. 11. l. 4. c. 17, 18.