[15] "Chaldea" or mat Kaldi generally referred to the low, marshy, alluvial land around the estuaries of the Tigris and Euphrates,[16] which at the time discharged their waters through separate mouths into the sea.
The Book of Jeremiah makes frequent reference to the Chaldeans (King James Version Chaldees following LXX Χαλδαίοι; in Biblical Hebrew as Kasdîm כַּשְׂדִּים).
Book of Isaiah 23:13 DRB states, “Behold the land of the Chaldeans, there was not such a people, the Assyrians founded it: they have led away the strong ones thereof into captivity, they have destroyed the houses thereof, they have brought it to ruin.” Unlike the East Semitic Akkadian-speaking Akkadians, Assyrians and Babylonians, whose ancestors had been established in Mesopotamia since at least the 30th century BC, the Chaldeans were not a native Mesopotamian people, but were late 10th- or early 9th-century BC West Semitic Levantine migrants to the southeastern corner of the region, who had played no part in the previous three millennia of Sumero-Akkadian and Assyro-Babylonian Mesopotamian civilization and history.
This was a period of weakness in Babylonia, and its ineffectual native kings were unable to prevent new waves of semi-nomadic foreign peoples from invading and settling in the land.
[21] Though belonging to the same West Semitic speaking ethnic group and migrating from the same Levantine regions as the earlier arriving Aramaeans, they are to be differentiated; the Assyrian king Sennacherib, for example, carefully distinguishes them in his inscriptions.
As a result, in late periods both the Babylonian and Assyrian dialects of Akkadian became marginalized, and Aramaic took its place across Mesopotamia, including among the Chaldeans, and later, also the southern Levant.
The main players in southern Mesopotamia during this period were Babylonia and Assyria, together with Elam to the east and the Aramaeans, who had already settled in the region a century or so prior to the arrival of the Chaldeans.
Important Kaldu tribes and their regions in southeastern Babylonia were Bit-Yâkin (the original area the Chaldeans settled in on the Persian Gulf), Bet-Dakuri, Bet-Adini, Bet-Amukkani, and Bet-Shilani.
During this time both the Babylonians and the Chaldean and Aramean migrant groups who had settled in the land once more fell completely under the yoke of the powerful Assyrian king Tiglath-Pileser III (745–727 BC), a ruler who introduced Imperial Aramaic as the lingua franca of the empire.
At the same time, Egypt began encouraging and supporting the rebellion against Assyria in Israel and Canaan, forcing the Assyrians to send troops to deal with the Egyptians.
While the Assyrian king was otherwise occupied defending his Iranian colonies from the Scythians and Cimmerians and driving the Egyptians from Canaan, Marduk-apla-iddina II (the Biblical Merodach-Baladan) of Bit-Yâkin, allied himself with the powerful Elamite kingdom and the native Babylonians, briefly seizing control of Babylon between 721 and 710 BC.
With the Scythians and Cimmerians vanquished, the Medes and Persians pledging loyalty, and the Egyptians defeated and ejected from southern Canaan, Sargon II was free at last to deal with the Chaldeans, Babylonians, and Elamites.
He was once more soundly defeated at Kish, and once again fled to Elam where he died in exile after one final failed attempt to raise a revolt against Assyria in 700 BC, this time not in Babylon, but in the Chaldean tribal land of Bit-Yâkin.
This prompted the enraged Assyrian king Sennacherib to invade and subjugate Elam and Chaldea and to sack Babylon, laying waste to and largely destroying the city.
Babylon was regarded as a sacred city by all Mesopotamians, including the Assyrians, and this act eventually resulted in Sennacherib's being murdered by his own sons while he was praying to the god Nisroch in Nineveh.
He conquered Egypt, Nubia and Libya and entrenched his mastery over the Persians, Medes, Parthians, Scythians, Cimmerians, Arameans, Israelites, Phoenicians, Canaanites, Urartians, Pontic Greeks, Cilicians, Phrygians, Lydians, Manneans and Arabs.
Shamash-shum-ukin (668–648 BC) had become infused with Babylonian nationalism after sixteen years peacefully subject to his brother, and despite being Assyrian himself, declared that the city of Babylon and not Nineveh or Assur should be the seat of the empire.
The alliance included the Babylonians, Persians, Chaldeans, Medes, Elamites, Sultans, Arameans, Israelites, Arabs and Canaanites, together with some disaffected elements among the Assyrians themselves.
After a bitter struggle lasting five years, the Assyrian king triumphed over his rebellious brother in 648 BC, Elam was utterly destroyed, and the Babylonians, Persians, Medes, Chaldeans, Arabs, and others were savagely punished.
However, after the death of the mighty Ashurbanipal (and Kandalanu) in 627 BC, the Neo-Assyrian Empire descended into a series of bitter internal dynastic civil wars that were to be the cause of its downfall.
Continual conflict among the Assyrians led to a myriad of subject peoples, from Cyprus to Persia and The Caucasus to Egypt, quietly reasserting their independence and ceasing to pay tribute to Assyria.
However, his position was still far from secure, and bitter fighting continued in the Babylonian heartlands from 620 to 615 BC, with Assyrian forces encamped in Babylonia in an attempt to eject Nabopolassar.
The Median Cyaxares had also recently taken advantage of the anarchy in the Assyrian Empire, while officially still a vassal of Assyria, he took the opportunity to meld the Iranian peoples; the Medes, Persians, Sagartians and Parthians, into a large and powerful Median-dominated force.
A new Assyrian king, Ashur-uballit II (612–605 BC), took the crown amidst the house-to-house fighting in Nineveh, and refused a request to bow in vassalage to the rulers of the alliance.
The Egyptians had belatedly come to the aid of Assyria, which they would have hoped to support as a secure buffer between Egypt and the new powers of Babylon, Medes and Persians, having already been raided by the Scythians.
His building activity at Babylon, expanding on the earlier major and impressive rebuilding of the Assyrian king Esarhaddon, helped to turn it into the immense and beautiful city of legend.
By 572, Nebuchadnezzar was in full control of Babylonia, Chaldea, Aramea (Syria), Phonecia, Israel, Judah, Philistia, Samarra, Jordan, northern Arabia, and parts of Asia Minor.
The Persians considered this Chaldean societal class to be masters of reading and writing, and especially versed in all forms of incantation, sorcery, witchcraft, and the magical arts.
[38] In the fifteenth century the term "Chaldeans" was first applied specifically to Assyrians living in Cyprus who entered a union with Rome, and no longer merely with reference to their language but the name of a new church.
These were used by the people themselves and their Persian, Armenian, Arab, Greek, Georgian and Kurdish neighbours both before and after the advent of Christianity in Iraq, Northeast Syria, Southeast Turkey and Northwest Iran.