At the end of the day, all accounts – the Assyrians, the Bible, and Herodotus, interpreted events. They didn't invent them.This is a good article and is well worth reading. It's in their premium section, but you can still read it with a free registration with Haaretz.
Something unexpected happened to the Assyrian army, which the people of the ancient Near East attributed to divine meddling.
The ancient kings had to keep their subjects and gods happy and propaganda was the most effective way to distort history and cover up failure. Sennacherib's failure to conquer Jerusalem was embarrassing and was over-compensated by grand reliefs on palace walls and extravagant claims of plunder. The fact that one of the main instigators of the Assyrian rebellion, Hezekiah, remained on the throne, albeit denuded of his wealth and women, may say it all.
As for the siege of Jerusalem, something remarkable happened there. I don't know what. The best story is the one in which the Angel of the Lord struck down the Assyrian army. Do what you will with it.
Past posts on Sennacherib's siege of Jerusalem are here and here and follow the links.
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