 Though belonging to the same West Semitic speaking ethnic group and migrating from the same Levantine regions like the earlier arriving Aramaeans, they are to be differentiated; the Assyrian king Sennacherib, for example, carefully distinguishes them in his inscriptions.The Chaldeans were able to keep their identity despite the dominant Assyro-Babylonian culture although some were not able to, as was the case for the earlier Amorites, Kassites and Suteans before them by the time Babylon fell in 539 BCE.The Chaldeans originally spoke a West Semitic language similar to but distinct from Aramaic.