Who were the Chaldeans?
The Chaldeans (Kaldu in Akkadian) were tribal groups who had settled in southern Babylonia by the early first millennium BCE, along with Arameans, often in the marshy region near the Persian Gulf. The largest Chaldean groups were organised as “houses” named after an ancestor, such as Bit-Yakin. One of their leaders, Merodach-baladan of Bit-Yakin, ruled Babylon for a time in the late 8th century BCE and resisted Assyria for years, as Assyrian royal inscriptions record at length. In the 7th century, Assyrian kings tried to control Babylonia by installing their own appointees, by direct rule and by force, and the region frequently rebelled.
The founder of the Neo-Babylonian dynasty, Nabopolassar, is usually called a Chaldean because of the later name “Chaldean dynasty”, but where he actually came from is debated. Some scholars place his origins in the region of Uruk; others suggest he was a Babylonian official rather than a tribal leader. His own inscriptions describe him as a man of humble origins, “son of a nobody”, who was raised by the god Marduk. That phrase suited a king without royal ancestry who needed divine support.
The Assyrian collapse
Assyria looked invincible under Ashurbanipal, who died around 631 BCE (some scholars prefer 627). After his death, civil strife and weakened control opened the way for rebellion. When the Assyrian-backed king of Babylon, known as Kandalanu, died in 627 BCE, Nabopolassar was proclaimed king in November 626 BCE, after winning control of Babylon in a struggle with Assyrian forces. He then spent years fighting Assyria for the cities of the north.
The Assyrian Empire did not fall to Babylon alone. The Medes, a power in what is now western Iran, attacked Assyria’s heartland in the 610s BCE and, according to the Babylonian Chronicle, captured the old religious capital of Ashur in 614. Nabopolassar met the Median king (named Cyaxares in Greek sources) after the fall of Ashur, and the Chronicle records that the two made an alliance. Medes and Babylonians together besieged Nineveh, which fell in 612 BCE. A rump Assyrian government under Ashur-uballit II held out at Harran with Egyptian support until about 609 BCE.
Later tradition, preserved through the Babylonian historian Berossus and reported by Josephus, says the alliance was sealed by the marriage of Nebuchadnezzar to a Median princess, called Amytis in Greek. That story may be genuine or invented, and it is best treated with caution. It did, however, reflect a real balance of power, in which Babylon took Assyria’s southern and western lands, while the Medes took the highlands.
From Nabopolassar to Nebuchadnezzar
Nabopolassar’s last years were spent campaigning on the Euphrates, and he died in August 605 BCE. His son Nebuchadnezzar, who had just led the army to victory at Carchemish, hurried back to Babylon and was crowned in early September. This was the smoothest transfer of power in the dynasty. Nebuchadnezzar had been named crown prince, and no rival is recorded. He then reigned for 43 years.
Babylon had no strict rule of primogeniture. A new king needed support from the army, the temples, and the families of the old cities. Strong rulers could secure their sons’ positions by giving them command and visible responsibility, as Nabopolassar did with Nebuchadnezzar. Weaker or less well-connected rulers could not.
The successors
Nebuchadnezzar died in 562 BCE, and the dynasty’s decline followed within six years.
- Amel-Marduk (562 to 560 BCE). The son of Nebuchadnezzar, whose name means “man of Marduk” (the Bible calls him Evil-merodach). He is remembered for releasing Jehoiachin of Judah from prison, according to the Hebrew Bible. Babylonian sources suggest that his reign was marked by court tension, and he was overthrown after about two years.
- Neriglissar (560 to 556 BCE). A senior official and Nebuchadnezzar’s son-in-law, who took the throne by force or by conspiracy. He campaigned in Cilicia in south-eastern Anatolia and carried out building work, but he died after a short reign.
- Labashi-Marduk (556 BCE). His young son, who ruled for only a few months. Later sources describe him as unfit for rule, but these accounts come from the men who removed him and should be read sceptically. He was killed in a conspiracy.
Nabonidus was then chosen as king. He was not a descendant of Nebuchadnezzar, and he came from a background linked with the northern city of Harran. His accession ended the Chaldean line. How much support he had from different groups is unclear, though he presents himself in inscriptions as the choice of the gods.
Why the line failed
Historians point to several factors. The dynasty was only two generations old when Nebuchadnezzar died, so it had few established traditions of succession. Like other Mesopotamian empires, it relied heavily on the personal authority of its king and on a small circle of officials and generals, which meant that a murder or coup could change the ruling family quickly. Great temple estates, such as those at Babylon and Uruk, had their own interests, and any king needed to keep them satisfied.
What the sources do not tell us is whether the rapid changes of 562 to 556 BCE were also the symptom of deeper weaknesses in the empire, such as strain from tribute, administration or conflict between the crown and priests. We know the outcomes much better than the motives. Whatever the underlying causes, the Persian conquest came only 17 years after Nabonidus took the throne.