20 All the people of the land rejoiced, and the city was calm, because Athaliah had been slain with the sword at the palace.

Read 2 Kings 11:20 Using Other Translations

And all the people of the land rejoiced, and the city was in quiet: and they slew Athaliah with the sword beside the king's house.
So all the people of the land rejoiced, and the city was quiet after Athaliah had been put to death with the sword at the king's house.
So all the people of the land rejoiced, and the city was peaceful because Athaliah had been killed at the king’s palace.