The Book of Jonah is widely accepted to be a social satire written in post-exilic times. However, recently, I stumbled upon an article from a (questionable) apologetics source claiming that Jonah is actually a historical account that can be corroborated by archaeological evidence.
The writer references Greek accounts of the size of Nineveh, language that is supposedly contemporary to its setting, and most interesting: that the time of Jonah’s supposed ministry (attested to in 2 Kings 14:25) correlates with the start of the Assyrian “Period of Stagnation”.
From what I understand, the writer’s argument is that because Jonah’s ministry happens around the same time that the Assyrians break with a 41-year long streak of constant warfare, the logical conclusion is that Jonah’s prophecy against Nineveh forced its then-king (Ashur-Dan III) to cease its military ambitions for a brief time.
Interestingly enough, the author further implies that the subsequent revolts and plagues that happen to Assyria are a direct punishment for Ashur-Dan’s choice in returning to warfare, thus bringing about a slightly-delayed fulfillment of Jonah’s prophecy.
This all makes for riveting pop history, but honestly, it all sounds pretty sus. Setting aside the writer’s obvious apologetics bent for a moment, is there any credence whatsoever to his historical claims? And if not, what other explanations might account for the temporary cessation of Assyrian campaigns after 41 years?
Jonah is not (nor does it try to be) a work of history. It was written to an audience well aware of both the fact that Assyria remained an expansionist military power through to the end, and the fact of Assyria's subsequent destruction. I'm going to quote myself in a different answer at some length with additions where necessary to address this question specifically.
Let's start by examining what the book of Jonah IS.
Jonah is a particularly neat book as Biblical literature goes... it's a succinct, clear, unambiguous, carefully plotted story. There might be various ideas the author is drawing on that come from various places, but it definitely seems to have a single author, motivating idea, and intentionality beyond what is found almost anywhere in the canon.
And what is this idea? It's a meditation on the limits of YHWH's forgiveness...
Jonah is willing to die under the condemnation of God rather than help the city repent, and when it does, basically refuses to accept its repentance and sits on a hill waiting for God to destroy it...
And we know what the Judahites and Israelites thought about Assyria... it wasn't good. See the entire book of Nahum (or the sections of 2 Kings where the wars are described). Or, if you want the story from the other angle, see the Lachish reliefs, where the Assyrians depict themselves beseiging the city of Lachish (see 2 Kings 18, where the captured city appears to have become the temporary headquarters of the invading Assyrian forces). According to the Assyrian pictographic account, prisoners were brought before the king to beg for their lives, then beheaded, thrown from towers, impaled on spikes, and flayed alive. (See also the annals of Sennacherib for a description of this campaign that agrees in most details with the account in 2 Kings--though both are putting their best 'spin' on the situation, and differ somewhat on the tribute arrangement.)
Jonah is a "what if" asking what it would take for God to have forgiven the ultraviolent Assyrians... and how the Assyrians' victims would have reacted to such forgiveness being granted to the repentant Assyrians.
This was its original context, and any attempt to make it fit somewhere in the historical record is doomed to failure on account of having missed the point entirely. I read through the linked article; chunks of the background were reasonably accurate, but once it got to the point of trying to convince us that Jonah was history, it went off the rails reasonably quickly.
To very briefly address the primary argument of the article, no, there is no evidence that Assyria ever renounced violence, no matter how briefly. The records show a nearly continuous pattern of campaigns occasionally broken up by material concerns, with Assyria's expansionist tendency only slowed by revolts, plagues, or the like.