Nabopolassar in the context of "Medo-Babylonian conquest of the Assyrian Empire"

The Neo-Babylonian Empire or Second Babylonian Empire, historically known as the Chaldean Empire, was the last polity ruled by monarchs native to ancient Mesopotamia. Beginning with the coronation of Nabopolassar as the King of Babylon in 626 BC and being firmly established through the fall of the Assyrian Empire in 612 - 609 BC, the Neo-Babylonian Empire was conquered by the Achaemenid Persian Empire in 539 BC, less than a century after the founding of the Chaldean dynasty.The defeat of the Assyrian Empire and subsequent return of power to Babylon marked the first time that the city, and southern Mesopotamia in general, had risen to dominate the ancient Near East since the collapse of the Old Babylonian Empire (under Hammurabi) nearly a thousand years earlier. The period of Neo-Babylonian rule thus saw unprecedented economic and population growth throughout Babylonia, as well as a renaissance of culture and artwork as Neo-Babylonian kings conducted massive building projects, especially in Babylon itself, bringing back many elements from the previous 2,000 years of Sumero-Akkadian culture.

The Neo-Babylonian Empire retains a notable position in modern cultural memory due to the portrayal of Babylon and its greatest king Nebuchadnezzar II in the Bible. The biblical account of Nebuchadnezzar describes his military campaign against the Kingdom of Judah, and in particular the Babylonian siege of Jerusalem in 587 BC which resulted in the destruction of Solomon's Temple and the subsequent Babylonian captivity. The Bible also describes the majesty of Nebuchadnezzar's rule and his sympathetic relationship with his Jewish captives. Babylonian sources describe Nebuchadnezzar's reign as a golden age that transformed Babylonia into the greatest empire of its time.

Nebuchadnezzar II, also Nebuchadrezzar II, meaning "Nabu, watch over my heir", was the second king of the Neo-Babylonian Empire, ruling from the death of his father Nabopolassar in 605 BC to his own death in 562 BC. Often titled Nebuchadnezzar the Great, he is regarded as the empire's greatest king, famous for his military campaigns in the Levant and their role in Jewish history, and for his construction projects in his capital of Babylon, including the Hanging Gardens of Babylon. Ruling for 43 years, Nebuchadnezzar was the longest-reigning king of the Babylonian dynasty. By the time of his death, he was among the most powerful rulers in the world.

Possibly named after his grandfather of the same name or after Nebuchadnezzar I, one of Babylon's greatest warrior-kings, Nebuchadnezzar II had already secured renown for himself during his father's reign, leading armies in the Medo-Babylonian conquest of the Assyrian Empire. At the Battle of Carchemish in 605 BC, Nebuchadnezzar inflicted a crushing defeat on an Egyptian army led by Pharaoh Necho II and ensured that the Neo-Babylonian Empire would succeed the Neo-Assyrian Empire as the dominant power in the ancient Near East. Shortly after this victory, Nabopolassar died and Nebuchadnezzar became king.

The Chaldean dynasty, also known as the Neo-Babylonian dynasty and enumerated as Dynasty X of Babylon, was the ruling dynasty of the Neo-Babylonian Empire, ruling as kings of Babylon from the ascent of Nabopolassar in 626 BC to the fall of Babylon in 539 BC. The dynasty, as connected to Nabopolassar through descent, was deposed in 560 BC by the Aramean official Neriglissar (r. 560–556 BC), though he was connected to the Chaldean kings through marriage and his son and successor, Labashi-Marduk (r. 556 BC), might have reintroduced the bloodline to the throne. The final Neo-Babylonian king, Nabonidus (r. 556–539 BC), was genealogically unconnected to the previous kings, but might, like Neriglissar, also have been connected to the dynasty through marriage.

Nebuchadnezzar (Babylonian cuneiform: Nabû-kudurri-uṣur, meaning "Nabu, watch over my heir"), also spelled Nebuchadrezzar, and most commonly known under the nickname Kudurru, was a governor of the city Uruk in Babylonia under the rule of Ashurbanipal (r. 669–631 BC) of the Neo-Assyrian Empire, appointed after the defeat of Shamash-shum-ukin of Babylon, Ashurbanipal's brother who had rebelled against Assyria, c.  648 BC. He was likely the son of the high priest Nabonassar.

In the reign of Ashurbanipal's son Sinsharishkun (r. 627–612 BC), the grave of Nebuchadnezzar was desecrated, with the perpetrators going so far as dragging his body through the streets of Uruk. This was done as a response to the anti-Assyrian activities of his two sons. In 2007, Assyriologist Michael Jursa identified Nebuchadnezzar as the father of Nabopolassar, the founder of the Neo-Babylonian Empire, who rebelled against Sinsharishkun in 626 BC (this being the anti-Assyrian activities). If Nabopolassar was his son, Nabopolassar would go on to name his own son, Nebuchadnezzar II, after his father.

The Battle of Carchemish was a battle fought around 605 BCE between the armies of Egypt, allied with the remnants of the Neo-Assyrian Empire, against the armies of Babylonia. The forces would clash at Carchemish, an important military crossing and trade city on the banks of the Euphrates River in modern-day Syria. Nebuchadnezzar II was given command of this Babylonian force while Nabopolassar, his father and the king of Babylonia, was still in Babylon. Necho II, the king of Egypt, led the Egyptian and Assyrian forces in the battle. The battle would end in a major defeat for the Egyptian and Assyrian forces. The defeat ended Egyptian influence in the Levant and led to Babylon expanding its domain to the borders of Egypt.

Sîn-šar-iškun (Neo-Assyrian Akkadian: 𒁹𒀭𒌍𒌋𒌋𒃻𒌦, romanized: Sîn-šar-iškun or Sîn-šarru-iškun, meaning "Sîn has established the king") was the penultimate king of Assyria, reigning from the death of his brother and predecessor Aššur-etil-ilāni in 627 BC to his own death at the Fall of Nineveh in 612 BC.

Succeeding his brother in uncertain, but not necessarily violent circumstances, Sîn-šar-iškun was immediately faced by the revolt of one of his brother's chief generals, Sîn-šumu-līšir, who attempted to usurp the throne for himself. Though Sîn-šumu-līšir was defeated relatively quickly, the instability caused by his revolt, combined with an ongoing interregnum in Babylonia in the south (neither Sîn-šar-iškun nor Sîn-šumu-līšir had formally proclaimed themselves as kings of Babylon) might be what made it possible for Nabopolassar, a southerner of unclear origin, to rise up and seize power in Babylonia. Sîn-šar-iškun's inability to defeat Nabopolassar, despite repeated attempts over the course of several years, allowed Nabopolassar to consolidate power and form the Neo-Babylonian Empire, restoring Babylonian independence after more than a century of Assyrian rule.