Isaiah 13:1-5. “The burden of Babylon, which Isaiah the son of Amoz did see. Lift ye up a banner upon the high mountain, exalt the voice unto them, shake the hand, that they may go into the gates of the nobles. I have commanded My sanctified ones, I have also called My mighty ones for Mine anger, even them that rejoice in My highness. The noise of a multitude in the mountains, like as of a noise of the kingdoms of nations gathered together: the Lord of hosts mustereth the host of the battle. They come from a far country, from the end of heaven, even the Lord, and the weapons of His indignation, to destroy the whole land.”
Chapters 13-23 consist of prophecies about Israel’s surrounding Gentile nations. Coming after the prophecies of the Millenial Kingdom, in which Jesus Christ, Messiah, will have all authority over the entire world, the doom of these nations under His anger is listed.
Babylon comes first. It includes the rule of the Chaldeans, which succeeded that of Assyria. Verses 2-5 are descriptive of the Medes, who are mentioned in verse 17, and of the Persians; verse 4 mentions kingdoms (plural). These powers are called “My consecrated ones” because they were chosen by God for the fulfillment of the destruction of Babylon (verse 3). They didn’t necessarily know that they were being used of God, but the Persians did destroy idols , and Cyrus the Persian did rejoice in the recognition of God (ch. 44:28; 45:1, and Ezra 1:1-4). The Medo-Persian powers were to be “the weapons of His indignation, to destroy the whole land,” the land of the Chaldeans.
You can verify all this by reading about the history of Babylon, including its present state of non-existence. God used other countries to bring Israel back to Himself, but those countries paid the price according to their mistreatment of His people.