In Isaiah 36-37, the Neo-Assyrian king Sennacherib invades Judah in the 14th year of Hezekiah and conquers all of its fortified cities, and an Assyrian high official (the רַב־שָׁקֵה rab-šāqē, rendering Akkadian rab-šāqê, often translated as 'chief cupbearer' but the meaning of šāqû in this context is actually unclear) then brings his army from Lachish to Jerusalem, to king Hezekiah, and politely but at great length requests its surrender. Hezekiah takes this pretty poorly, and after some speeching, Isaiah, his pet prophet, tells him not to surrender. An angel shows up in the night and kills 185,000 Assyrians, who wake up the next morning to find that all the corpses are dead—the Assyrian army is forced to withdraw.
The same event is described in 2 Kings 18:13-19:36: in the 14th year of Hezekiah, Sennacherib conquers the fortified cities of Judah, and now it's Hezekiah who sends a delegation to Lachish, begging Sennacherib not to attack Jerusalem. Sennacherib exacts 300 talents of silver (about 10 tons) and 30 talents of gold (about a ton) in tribute, for which Hezekiah has to strip the doors and pillars of the Temple. After this the rab-šāqê nonetheless shows up with his army, and the same things happen as in Isaiah, more or less verbatim; the angel again kills 185,000. This whole section is certainly secondary and taken from Isaiah.
The retread in Chronicles (2 Chronicles 32:1-23) also leaves out the tribute, and the angel now kills every valorous warrior, leader, and commander in the Assyrian camp.
So did this really happen? Hezekiah comes out of it looking pretty bad—unacceptably bad, clearly, in the eye of the editors who removed any mention of tribute from two of the takes, which suggests it probably was based on a real event.
And it was! This is Sennacherib's third campaign, which is related in over a dozen different texts attested in literally hundreds of cuneiform inscriptions (e.g. RINAP 3 4, starting on line 32). Sennacherib was responding to a large-scale revolt against Assyrian dominance in the Levant in 701 BCE, in which, among other things, the aristocracy of the Philistine city of Ekron deposed their king Padî and handed him over to Hezekiah (ᵐḫa-za-qi-a-ú). Sennacherib suppresses the revolt and finally lays siege to Jerusalem, and the tribute he receives from Hezekiah is:
30 talents of gold, 800 talents of silver, choice antimony, large blocks of ..., ivory beds, armchairs of ivory, elephant hide(s), elephant ivory, ebony, boxwood, garments with multi-colored trim, linen garments, blue-purple wool, red-purple wool, utensils of bronze, iron, copper, tin, (and) iron, chariots, shields, lances, armor, iron belt-daggers, bows and uṣṣu-arrows, equipment, (and) implements of war, (all of) which were without number, together with his daughters, his palace women, male singers, (and) female singers
(The Akkadian uses biltu for 'talent', but in this context it's the same thing as the Biblical כִּכָּר kikkār.)
Hezekiah pledges his loyalty to Sennacherib, and the Assyrians leave. The conquered Judean cities are divided up among Ashdod, Ekron, and Gaza, Philistine cities who remained loyal to Sennacherib.
It's interesting to compare what gets mentioned in each account and what doesn't. The sequence of events must have been as follows:
Hezekiah joins a large-scale anti-Assyrian revolt: not mentioned in the Bible, where the Assyrians just show up for no apparent reason.
Sennacherib's troops reconquer the rebellious territory with ease: mentioned in both, in both cases to play up the power of the Assyrian army.
Sennacherib lays siege to Jerusalem: only implicitly in the Bible, where the rab-šāqê brings his army but never uses it.
During the siege, disease strikes the Assyrian army, causing many casualties, and because of this, Sennacherib isn't able to take Jerusalem: not mentioned in Sennacherib's version, but there's no other way to explain why he wouldn't have sacked the city and deposed Hezekiah—Jerusalem was well-positioned to weather sieges, but the Assyrian army was pretty good at its job.
As a compromise, Sennacherib accepts tribute from Hezekiah to lift the siege: not mentioned in two of the Biblical accounts, and the size of the tribute is probably exaggerated in Sennacherib's version.
Hezekiah (re)pledges loyalty to Sennacherib, and the conquered Judean cities are given to loyal Philistines: not mentioned in the Bible.
The Assyrian army leaves.
Serious people are generally aware that the Bible has a patchy transmission history and that it was written and edited by people with agendas that rarely included the objective relaying of history. The great advantage of cuneiform texts is that they (mostly) don't have a transmission history—we have them just as they were written down—but maybe partly because of that people still often forget that official histories come with their own agenda.