Background: The Greek historian Herodotus is considered “History’s First Historian”. In the account below, he describes the organization of the Persian state under Darius the Great.
III.88: Thus was Darius, son of Hystaspes, appointed king; and, except the Arabians, all they of Asia were subject to him; for Cyrus, and after him Cambyses, had brought them all under. The Arabians were never subject to the Persians, but had a league of friendship with them from the time when they brought Cambyses on his way as he went into Egypt; for had they been unfriendly, the Persians could never have made their invasion.
And now Darius contracted marriages of the first rank, according to the notions of the Persians: to wit, with two daughters of Cyrus, Atossa and Artystone; of whom, Atossa had been twice married before, once to Cambyses, her brother, and once to the Magus, while the other, Artystone, was a virgin. He married also Parmys, daughter of Smerdis, son of Cyrus; and he likewise took to wife the daughter of Otanes, who had made the discovery about the Magus. And now when his power was established firmly throughout all the kingdoms, the first thing that he did was to set up a carving in stone, which showed a man mounted upon a horse, with an inscription in these words following: “Darius, son of Hystaspes, by aid of his good horse” (here followed the horse’s name), “and of his good groom Oibares, got himself the kingdom of the Persians.”
III.89: This he set up in Persia; and afterwards he proceeded to establish twenty governments of the kind which the Persians call satrapies, assigning to each its governor, and fixing the tribute which was to be paid him by the several nations. And generally he joined together in one satrapy the nations that were neighbors, but sometimes he passed over the nearer tribes, and put in their stead those which were more remote. The following is an account of these governments, and of the yearly tribute which they paid to the king: Such as brought their tribute in silver were ordered to pay according to the Babylonian talent; while the Euboic was the standard measure for such as brought gold. Now the Babylonian talent contains seventy Euboic minae. During all the reign of Cyrus, and afterwards when Cambyses ruled, there were no fixed tributes, but the nations severally brought gifts to the king. On account of this and other like doings, the Persians say that Darius was a huckster, Cambyses a master, and
Cyrus a father; for Darius looked to making a gain in everything; Cambyses was harsh and reckless; while Cyrus was gentle, and procured them all manner of goods…
(The remainder of the passage lists the contents of the tribute paid by the regions of the empire.)