The book of Isaiah in the Old Testament has two sets or categories of prophecies:
 

Isaiah has many statements confirmed correct.

Isaiah 44:9-20 criticises the stupidity of worshipping idols. Every ancient nation around Israel from Spain to Persia, tens of millions of people, worshipped idols. Yet all such worship eventually vanished. Some idols survive as museum pieces — not as gods worshipped. Isaiah’s counsel is thus confirmed.

In the 19^th century critics rejected the existence of Sargon of Assyria. (Isaiah 20:1) In 1843 archaeologists excavated his palace at Khorsabad and various inscribed records. They confirmed that Sargon was a powerful Assyrian king who reigned 721-705 BC.

It’s been estimated that 30% of people in Western countries take astrology seriously. Yet Isaiah condemned the trust Babylon placed in astrologers:
 

That astrology is worthless for predicting the future of individuals and of nations is confirmed by science. The Weekend Australian, for example, reported on "astrological bunk". (1985, December 14-15)

30% of people are wrong but Isaiah is right.

Isaiah condemned excessive drinking of wine. (5:22) Tens of millions of people ignore this to their own detriment. Isaiah doesn’t mention health or psychological reasons, but health reasons are given in the book of Proverbs. Isaiah also condemned bribery. (5:23) Again, millions ignore this and the result is "corruption" in law and politics to the detriment, sometimes, of entire nations.

People often justify their moral lapses by relabelling evil as good. One Nazi leader called the Nazi murderers of millions of people in Eastern Europe "decent". Parents who sexually abuse their children often say, "I saw nothing wrong with it." By considering a large range of moral evils — thievery, lying, immorality, terrorism, smoking, etc — we see that everyone performs the self-deception of labelling evil as good and good as evil. Such moral relabelling was common in Isaiah’s time too and he condemned it:
 

Prior to the finding of the Dead Sea Scrolls the oldest manuscript of Isaiah was a 10^th century CE copy. Skeptics could therefore claim that Isaiah was revised and changed century after century and the original was very different to what's in our Bibles.

However, the Dead Sea Scrolls discovered from 1947 to 1956 included a copy of Isaiah in Hebrew copied in the 2^nd century BCE. It revealed that the text stayed almost constant over the centuries. Geisler and Nix (1968) compared the Dead Sea Scroll of Isaiah Chapter 53 with the Masoretic Text of the tenth century. Chapter 53 has 166 words. In 1,000 years only one word was added, the word "light" to verse 11. This confirmed what Isaiah predicted:
 

This was a bold prophecy considering that both Assyria and Babylon — the world’s "super powers" around 700 BCE and 600 BCE respectively — tried to extinguish the Jews and their worship. Furthermore, in 2001 translation of the whole Bible reached 392 languages, which means Isaiah is available in at least that many — "the word of our God will stand forever."
 

Isaiah was a prophet who lived in Jerusalem. He became a prophet in the last year of the reign of King Uzziah of Judah in 740 BCE. (6:1) Isaiah was married and had two sons. The last historical event he mentions is the death of King Sennacherib of Assyria (37:37-38) which occurred in 681 BCE.

Isaiah's prophetic ministry lasted 60 years and overlapped the reigns of five kings of Judah:

Uzziah        791-740    (Isaiah 1-6)
Jotham        750-732    (Isaiah 1-6)
Ahaz           735-715    (Isaiah 7-14)
Hezekiah    727-698    (Isaiah 15-39)
Manasseh    698-642

When Isaiah was young the Old Testament prophets Hosea, Micah, Amos and Joel were active. After his death there were no prophets for fifty years. Then came Jeremiah, Ezekiel, Daniel, Obadiah, Zephaniah and Habakkuk.

The major political events of Isaiah's time included:
 

Chapters 40-66 are set in the time of the Babylonian Empire. In 605-585 BCE the Babylonians deported the Jews in a series of invasions resulting in the "seventy-year-captivity". Isaiah 40-66 was written to comfort the captives and to predict their release by Cyrus of Persia who conquered Babylon in 539 BCE. This occurred 140 years after Isaiah's death.
 
 

Many scholars argue that chapters 40 to 66 were not written by Isaiah but by at least one later writer and the various works were subsequently combined. This is the skeptic’s conclusion — since if Isaiah around 700 BCE wrote about the Jewish captivity in Babylon, which started about 600 BCE, and even named Cyrus of Persia (44:28; 45:1) who released the Jews in 537 BCE, it would imply prophecy inspired by God.

Conservative scholars, in contrast, argue that the book of Isaiah has a literary structure and unity that implies one author. For example:
 

Conservative scholars also point to various unifying features such as the phrase "Holy One of Israel". It occurs 12 times in chapters 1 to 39, 13 times in chapters 40 to 66 and only five times in the rest of the Old Testament. (Douglas et al 1982)
 

The New Testament treats Isaiah as one book and uses Isaiah’s name 22 times. However, that’s not relevant evidence of its unity to skeptics since to accept it is to accept the authority of the New Testament which skeptics don’t accept.
 
 

Trying to dispose of Isaiah’s accurate prophecies by dividing Isaiah into two or three books doesn’t suffice because the alleged "first" Isaiah also has true prophecies fulfilled centuries later.

For example regarding the Philistines:
 

This predicts the extinction of the Philistines. The prophet Amos concurs: "…the remnant of the Philistines shall perish." (Amos 1:8) The Philistines get lost to history after 500 BCE:
 

Another prophecy is about Babylon:
 

Funk & Wagnalls says, "The temples [of Babylon] continued in use for a time, but the city became insignificant and almost disappeared before the coming of Islam in the 7^th century AD."

Alexander the Great tried to overturn Isaiah’s prophecy. Funk and Wagnall’s says, "Alexander the Great captured the city in 330 BC and planned to rebuild it and make it the capital of his vast empire…"

Alexander conquered lands from North Africa to India and then planned to turn west and conquer Europe. In 323 BCE emissaries from many Western lands visited him. Babylon would have become the capital of the world utterly refuting Isaiah.

Instead, the military genius who ruled the largest ancient empire came to ruin. Alexander died, aged only 33, and his empire disintegrated and Isaiah’s prophecy triumphed.

19^th and 20^th century visitors to Babylon sometimes commented on its desolation and the howling of jackals among the ruins.
 
 

Some sectarian religions give many of Isaiah’s prophecies two fulfilments. They might give Isaiah's denunciation against Jerusalem a second application against Christendom or against the United States. Isaiah’s prophecies of doom against various nations like Babylon are similarly given parallels with modern nations or modern institutions.

Sectarian prophecies based on such a double-fulfilment notion have always failed. Furthermore, Isaiah nowhere hints at multiple meanings to "Israel", "Babylon", "Assyria", etc.

Therefore I conclude that Isaiah intended one fulfilment for his predictions.

Isaiah, however, contains two groups of prophecies. I do not mean the prophecies for the Assyrian period and Babylonian/Persian period.
Rather the two sets I refer to are:
 

In chapter 1, Isaiah is concerned with Jerusalem of his time and the immediate future.

Chapter 2 introduces "another vision that Isaiah…saw". It's about the distant future, the "last days" or "latter days":
 

The phrase "the last days" occurs 14 times in the Old Testament and five times in the New Testament:

1 Nebuchadnezzar’s empire of Babylon;
2 Persian Empire;
3 Empire of Alexander the Great;
4 Roman Empire.

Nebuchadnezzar’s vision culminates with the "kingdom of God" replacing the fourth empire and lasting forever. The "last days" therefore commence during the time of the Roman Empire.

Another clue is in Micah. The prophet Micah associates the "last days" with a ruler from Bethlehem who: "shall be great to the ends of the earth." (Micah 4:1 to 5:4)

The New Testament is more specific. It says the "last days" had started in the year Jesus died. At Pentecost after Jesus’ death the Apostle Peter quoted the prophet Joel:
 

In his second letter Peter again discusses the "last days" (2 Peter 3:3) and says that the world will be destroyed by fire. Peter adds:
 

This suggests that "the last days" refer to thousands of years — the plural implies at least two "days" or 2,000 years.

The Old Testament implied that the "last days" would start after three great empires had come and gone and a ruler out of Bethlehem becomes, "great to the ends of the earth." The New Testament clarifies this and suggests the "last days" started by 33 CE and would go for thousands of years.
 
 

Prophecies about the immediate future were relevant for Isaiah's immediate audience because the hearers would see some predictions fulfilled and could therefore know the message was reliable. This gave them the option of heeding the ethics Isaiah taught and returning to God. (e.g. 1:2-27; 5:7-12; 10:1-3)

Prophecies about the distant future were also relevant to Isaiah's immediate audience because such prophecies offered hope that the final result would be OK — all setbacks and all evil were temporary and God would triumph.

People living much later, in the actual "last days", would also find Isaiah relevant because they would experience some fulfilments in their time and could therefore also see Isaiah as "inspired" and trust in the predictions still to be fulfilled.

Isaiah alternates between the two sets of prophecies.  Chapter 1 applies to his time. Chapter Two introduces the distant "last days". Many chapters have both categories — verses about the immediate future and verses about the distant future.

A provisional list of Isaiah's predictions for the distant future (i.e. for the "last days"), using in most cases the New Testament as a guide, follows:

Sometimes the New Testament refers to Isaiah and applies the reference to the Christian era in cases where Isaiah is not predicting the distant future. For example:
 

Compare:

Such uses of Isaiah are made when a similar situation recurs in the Christian era or when people repeated the evils of earlier times and the same condemnation therefore fitted them. For example, if someone in the 21^st century advocates Nazism I might quote Winston Churchill’s criticisms of Nazism, not to imply that Churchill prophesied about the specific 21^st-century individual but because the same condemnation of the same evil is valid across time. Other examples of applying Isaiah’s words when similar situations recur are:

    Isaiah   6:9-10             Matthew 13:14-15
                40:6-8             1 Peter 1:22-25
                52:11              2 Corinthians 6:17
                65:1-2             Romans 10:20-21
 
 

Returning, now, to Isaiah’s two categories of prophecies. The "last days" would, as we saw in Isaiah 2 and Daniel 2, culminate in world peace under God's rule.

Isaiah's long-range predictions reveal events leading to that world peace and necessary to achieve it. These events include the life of a righteous "suffering servant".

Isaiah mentions five servants of God:

The suffering servant in contrast is "righteous" and "suffered for our iniquities". He is without "deceit in his mouth" and "had done no violence". Isaiah 53 reads like the life of Jesus as in the New Testament.

Isaiah gives an idea of how widely this "servant" would be known:
 

This prediction is similar to what is predicted about the ruler from Bethlehem in the last days, "he shall be great to the ends of the earth." (Micah 4:1 - 5:4) This appears fulfilled as Christianity expanded and kings and nations converted to Christianity.

Because some of Isaiah’s other prophecies were about King Cyrus of Persia some people think the "suffering servant" refers to Cyrus. However, Cyrus is called God’s "anointed" and "shepherd" (44:28 - 45:1-7; 41:25) but not God’s "servant".

Such phrases as "suffered for our iniquities" and "done no violence" and "righteous" do not describe Cyrus:
 

Cyrus was anointed or chosen to crush the Babylonian Empire and send the exiled Jews back to Israel. Cyrus fulfilled that but not Isaiah's other prophecies such as:
 

The New Testament says:
 

This prophecy is from Isaiah 7:14 and will be discussed separately.
 
 

Accurate history, accurate prophecy, and ethics that promote human good — and much of this still relevant in the third millennium — is evidence Isaiah was inspired by someone whose understanding is unsearchable:
 

Douglas, J D et al (Editors) 1982, New Bible Dictionary (Second Edition), Inter-Varsity Press, England, pp. 521-527.
Funk & Wagnall’s New Encyclopedia 1983, Volume 3, Babylon.
Geisler, N L & Nix, W E 1968, A General Introduction to the Bible, Moody, USA.
Nolting, P F A Prophetic Time-Term, The Journal of Theology, Volume 24, September 1984, Number 3, pp. 25-38.
The Bible, Revised Standard Version, 1952.
The Companion Bible 1972, Bagster & Sons, Great Britain, p. 930.
Thompson, D Giving Goliath His Due, Time, August 29, 1988, pp. 58-59.