The Chaldeans appear repeatedly in the later Old Testament. The biblical writers often use the term in connection with the Babylonian armies that threatened and eventually conquered Judah.
Second Kings, Chronicles, Jeremiah, Ezekiel, Habakkuk, and Daniel all reflect the growing importance of the Chaldeans. Their conquest of Jerusalem and destruction of the Temple in 586 BC brought the kingdom of Judah to an end and began the major phase of the Babylonian exile.
Ezekiel 23:16 describes Jerusalem turning toward the Chaldeans, while Habakkuk portrays them as a powerful and terrifying nation raised up as an instrument of judgment. Daniel uses the term in both ethnic and professional contexts within the Babylonian court.