 and by classical writers, such as Strabo.The disappearance of the Chaldeans as an ethnicity and Chaldea as a land is evidenced by the fact that the Persian rulers of the Achaemenid Empire (539–330 BCE) did not retain a province called "Chaldea", nor did they refer to "Chaldeans" as a race of people in their written annals.This is in contrast to Assyria, and for a time Babylonia also, where the Persians retained the names Assyria and Babylonia as designations for distinct geo-political entities within the Achaemenid Empire.