Babylonian astrology

In Babylon as well as in Assyria as a direct offshoot of Babylonian culture, astrology takes its place as one of the two chief means at the disposal of the priests (who were called bare or "inspectors") for ascertaining the will and intention of the gods, the other being through the inspection of the livers of sacrificial animals (see omen).

Babylonian astrology was the first organized system of astrology, arising in the second millennium B.C. There is speculation that astrology of some form appeared in the Sumerian period in the 3rd millennium BC, but the isolated references to ancient celestial omens dated to this period are not considered sufficient evidence to demonstrate an integrated theory of astrology. The history of scholarly celestial divination is therefore generally reported to begin with late Old Babylonian texts (c. 1800 B.C.), continuing through the Middle Babylonian and Middle Assyrian periods (c. 1200 B.C.).

By the 16th century B.C. the extensive employment of omen-based astrology can be evidenced in the compilation of a comprehensive reference work known as Enuma Anu Enlil. Its contents consisted of 70 cuneiform tablets comprising 7,000 celestial omens. Texts from this time also refer to an oral tradition - the origin and content of which can only be speculated upon. At this time Babylonian astrology was solely mundane, and prior to the 7th century B.C. the practitioners' understanding of astronomy was fairly rudimentary. Because of their inability to accurately predict future celestial phenomena and planetary movement very far in advance, interpretations were done as the phenomena occurred or slightly before. By the 4th century, however, their mathematical methods had progressed enough to calculate future planetary positions with reasonable accuracy, at which point extensive ephemerides began to appear.

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