Paul W. answered 12/07/19
Dedicated to Achieving Student Success in History, Government, Culture
Not all questions can be answered with either the word 'True' or the word 'False'!
The answer is 'Kinda True'. It's definitely true that the Chaldeans, a Semitic people who lived in southeastern Mesopotamia, participated in the capture and sacking of the Assyrian capitol city of Nineveh in the year 612 B.C.E. / B.C.
The 'Kinda' part concerns that fact that the Chaldeans were only one among a COALITION of peoples who captured and sacked Nineveh in 612 B.C.E. / B.C. The coalition, made up of peoples whom the Assyrians had conquered and ruled, included, along with the Chaldeans, the Babylonians, Cimmerians, Medes, Persians, and Scythians.
In 627 B.C.E. / B.C. the last of the great Assyrians kings, Ashurbanipal, died. Unfortunately for the Assyrian Empire, the Assyrians couldn't agree on who should be the next king. Factions formed around the different Royal Family members who thought that they should become the next ruler of the Assyrian Empire and civil war broke out.
With the Assyrians busy fighting one another, the peoples whom the Assyrians ruled saw their opportunity to regain their freedom. A revolt broke out in the Assyrian Empire in 616 B.C.E. / B.C. and spread rapidly. None of the different peoples who made up the population of the Assyrian Empire were capable of freeing themselves on their own. But, recognizing their common goal of overthrowing Assyrian rule, they agreed among themselves to cooperate, forming an anti-Assyrian Coalition / Alliance. Their success was demonstrated by their ability to capture the heavily fortified capitol of the Assyrian Empire, the city of Nineveh.
The fall of Nineveh in 612 B.C.E. / B.C. marked the end of Assyria as a major power in the Ancient Near East / Middle East. Never again afterwards would the Assyrians conquer other peoples to create an empire. Ironically, instead the Assyrians would become one among many other peoples in somebody else's empire...