In our study of Isaiah chapter thirteen, we look at the judgment of God on Babylon. We will see that this chapter contained a prophecy for the people of Isaiah's time as well as a prophecy for us and the last days.
"An oracle concerning Babylon that Isaiah son of Amoz saw:" NIV translation
The word "oracle" means burden or judgment and we see, here, that God is going to use the prophet to proclaim judgment on the Babylonian kingdom. This kingdom was based in what is the country of Iraq today.
"Raise a banner on a bare hilltop, shout to them; beckon to them to enter the gates of the nobles. I have commanded my holy ones; I have summoned my warriors to carry out my wrath - those who rejoice in my triumph." NIV translation
We have seen where the Assyrians were used to judge Israel and Babylon was used to judge Assyria. Now, we see that God is calling an army to overthrow the kingdom of Babylon. We must remember that the word "Holy" refers to something or someone that is set apart for God's service and not necessarily His people.
"Listen, a noise on the mountains, like that of a great multitude! Listen, an uproar among the kingdoms, like nations massing together! The Lord Almighty is mustering an army for war. They come from faraway lands, from the ends of the heavens - the Lord and the weapons of his wrath - to destroy the whole country." NIV translation
The prophet assures God's people that He is assembling a coalition of nations (speaking of the Media-Persian empire) to bring down Babylon. This prophecy has both happened and yet is to happen again. The Babylon of Isaiah's day was defeated by the Medes and the Persians. The new Babylon will be dealt with in the future as described by John in Revelation 17.