According to biblical archaeological theory, Siloam tunnel and the Broad Wall in Jerusalem were built by Hezekiah in preparation for the impending siege.

In 720 BC, the Assyrian army captured Samaria, the capital of the northern Kingdom of Israel, and carried away many Israelites into captivity.

He re-captured Philistine-occupied lands in the Negev desert, formed alliances with Ascalon and Egypt, and made a stand against Assyria by refusing to pay tribute.

Hezekiah gathered the citizens in the square and encouraged them by reminding them that the Assyrians possessed only "an arm of flesh", but the Judeans had the protection of Yahweh.

According to 2 Kings 18, while Sennacherib was besieging Lachish, he received a message from Hezekiah offering to pay tribute in exchange for Assyrian withdrawal.

In an attempt to demoralize the Judeans, the field commander announced to the people on the city walls that Hezekiah was deceiving them, and that Yahweh could not deliver Jerusalem from the king of Assyria.

During the siege, Hezekiah dressed in sackcloth (a sign of mourning), but the prophet Isaiah assured him that the city would be delivered and Sennacherib would fail.

[8] The text of the prism boasts how Sennacherib destroyed 46 of Judah's cities and trapped Hezekiah in Jerusalem "like a caged bird."

The text goes on to describe how the "terrifying splendor" of the Assyrian army caused the Arabs and mercenaries reinforcing the city to desert.

After he besieged Jerusalem, Sennacherib was able to give the surrounding towns to Assyrian vassal rulers in Ekron, Gaza and Ashdod.

[10] Some Biblical scholars take this to an allusion that the Assyrian army suffered the effects of a mouse- or rat-borne disease such as bubonic plague.