 In the case of the Assyrians in particular, Achaemenid records show Assyrians holding important positions within the empire, particularly with regards to military and civil administration.This absence of Chaldeans from the historical record continues throughout the Macedonian Empire, Seleucid Empire, Parthian Empire, Roman Empire, Sassanid Empire, Byzantine Empire and after the Arab Islamic conquest and Mongol Empire.By the time of Cicero in the 2nd century BCE, "Chaldean" appears to have completely disappeared even as a societal term for Babylonian astronomers and astrologers; Cicero refers to "Babylonian astrologers" rather than Chaldean astrologers.