When the text was written
- 1 720 BCE — Isaiah 1-39: the Assyrian crisis material
- 2 545 BCE — Isaiah 40-55, on the mainstream critical dating
- 3 515 BCE — Isaiah 56-66: addressed to a community back in the land
- 4 125 BCE — The Great Isaiah Scroll copied at Qumran — a manuscript date, not an authorship date
When the event happened
- 1 740 BCE — Isaiah’s call, in the year King Uzziah died (Isaiah 6)
- 2 722 BCE — Samaria falls; the northern kingdom ends
- 3 701 BCE — Sennacherib’s campaign in Judah; Jerusalem besieged
- 4 586 BCE — Jerusalem destroyed and the temple burned
- 5 539 BCE — Cyrus takes Babylon
- 6 538 BCE — The decree of Cyrus and the first return
One book, two hundred years of history, and a dispute about authorship that this chart is designed to make visible rather than to settle.
The lower band marks events that are datable from records made outside the biblical tradition. The upper band marks when the sections of the book of Isaiah are held to have been composed — on the mainstream critical division of the book into three parts. If you hold the traditional single-author position, the upper band is wrong in a specific and interesting way, and seeing exactly how wrong is more useful than being told the conclusion.
The events
722 BCE — Samaria falls. The northern kingdom ends and its population is deported. Assyrian royal inscriptions record the capture; the biblical account is in 2 Kings 17. This is the world Isaiah 1 to 39 is speaking into.
701 BCE — Sennacherib’s campaign in Judah. Recorded on Sennacherib’s own clay prisms, illustrated on the reliefs from his palace, and narrated from the other side in Isaiah 36 to 37. The source record attached to this page is the prism. The dossier on this site works through the disagreement between the two accounts.
586 BCE — Jerusalem destroyed. Isaiah 1 to 39 does not describe this; Isaiah 40 onwards addresses an audience for whom it has already happened. That change of situation is the observation the three-part division was built on.
539 BCE — Cyrus takes Babylon. Isaiah 44:28 and 45:1 name him. On the traditional reading, that name was written roughly a century and a half before the man arrived. On the critical reading, it was written by someone watching him arrive.
538 BCE onward — the return. Ezra 1 connects the decree of Cyrus to the rebuilding, and Isaiah 56 to 66 addresses a community back in the land and disappointed by it.
The text markers, and what they assume
Three text markers correspond to the three-part division. The first sits in the eighth century, with the Assyrian crisis. The second sits just before 539, in the exile, with Cyrus on the horizon. The third sits after the return.
A fourth marker sits far later, around the second century BCE, for the copying of the Great Isaiah Scroll found at Qumran. That marker is not an authorship claim and should not be read as one. It records a manuscript: the earliest surviving physical copy of the book, containing all sixty-six chapters continuously with no division at chapter 40. What it proves is that the book had been assembled as a unit by then. What it cannot prove, in either direction, is who wrote which part four hundred years earlier — and the frequency with which it is cited as though it could is the main reason it is on this chart.
The honest summary
If the three text markers are in the right places, Isaiah is an anthology assembled over two centuries and the naming of Cyrus is contemporary reference. If all three belong at the leftmost position, the book contains a named prediction across a hundred and fifty years. No manuscript, inscription or excavation currently distinguishes between those two accounts, because the evidence that would do so — a copy of the book from before 539 — does not exist and almost certainly never will.
What can be examined is the internal evidence, and that is what the book overview of Isaiah sets out. The method note on how we date a text explains the reasoning the upper band depends on.