Nebuchadnezzar’s general was sorting out the captives–who was too poor to bother with, who was coming to Babylon–when he came to Jeremiah. He was all, You’re cool, dude. If you want to come with us, you’re welcome. If you want to stay here, that’s cool too.
Jeremiah stayed. He went to live with Gedaliah, whom Nebuchadnezzar had appointed governor of Judah.
When all the Judeans who had fled to other lands like Moab and all the troops who had been stationed in the hinterlands heard that the war was over and Jerusalem had fallen, they made their way to Mizpah, where Gedialiah was headquartered to figure out what to do next. So they all settled down and eked out a living.
However, trouble was afoot. General Johanan tried to warn Gedaliah that this dude, Ishmael, who claimed he had royal blood, was gunning for him, but Gedaliah ignored him.