I think some of the answer is found in the Introductions to both books that I found at the USCCB’s on-line Bible. First the Introduction to Jeremiah, then Baruch, his secretary.
The Book of Jeremiah combines history, biography, and prophecy. It portrays a nation in crisis and introduces the reader to an extraordinary person whom the Lord called to prophesy under the trying circumstances of the final days of the kingdom of Judah. Jeremiah was born, perhaps about 650 B.C., of a priestly family from the village of Anathoth, two and a half miles northeast of Jerusalem. He was called to his task in the thirteenth year of King Josiah (Jer 1:2). Josiah’s reform, begun with enthusiasm and hope, ended with his death on the battlefield of Megiddo (609 B.C.) as he attempted to stop the northward march of the Egyptian Pharaoh Neco, who was going to provide assistance to the Assyrians who were in retreat before the Babylonians.
Nineveh, the capital of Assyria, fell in 612 B.C., preparing the way for the new colossus, Babylon, which was soon to put an end to the independence of Judah.
The prophet supported the reform of King Josiah (2 Kgs 22–23), but after the death of Josiah the old idolatry returned. Jeremiah opposed this as well as royal policy toward Babylon. Arrest, imprisonment, and public disgrace were his lot. In the nation’s apostasy Jeremiah saw the sealing of its doom. Nebuchadnezzar captured Jerusalem (598 B.C.) and carried King Jehoiachin into exile (Jer 22:24).
During the years 598–587, Jeremiah counseled Zedekiah in the face of bitter opposition. The false prophet Hananiah proclaimed that the yoke of Babylon was broken and a strong pro-Egyptian party in Jerusalem induced Zedekiah to revolt. Nebuchadnezzar took swift vengeance; Jerusalem was destroyed in 587 and its leading citizens sent into exile.
The prophet remained in Jerusalem, but was later forced into Egyptian exile. We do not know the details of his death. The influence of Jeremiah was greater after his death than before. The exiled community read and meditated on the lessons of the prophet; his influence is evident in Ezekiel, some of the psalms, Is 40–66, and Daniel. In the postexilic period, the Book of Jeremiah circulated in various editions.
Continued on the next post.