Zodiac 5

There are three main branches of astrology today, namely Western astrology, Indian or Jyotish astrology, and Chinese or East Asian astrology. The study of Western astrology and the belief in it, as part of astronomy, is first found in a developed form among the ancient Babylonians; and directly or indirectly through the Babylonians, it spread to other nations. It came to Greece about the middle of the 4th century B.C., reached Rome before the advent of the Christian era, and India with the Hellenistic Indo-Greek kingdoms.
With the introduction of Greek culture into Egypt, both astronomy and astrology were actively cultivated in the region of the Nile during the Hellenistic and Roman periods. Astrology was further developed by the Arabs from the 7th to the 13th century , and in the Europe of the 14th and 15th centuries astrologers were dominating influences at court. The Mayans of Central America and the Aztecs also developed their own form of astrology. Other cultures and civilizations around the world also developed their own astrological systems independently.
The terms astrology and astronomy have long been closely related. An Astrologer is an interpreter of celestial phenomena, while an Astronomer is a predictor of celestial phenomena. Astrology itself can be divided into two camps, comprised of "natural astrologers" (i.e. astronomers) who study the motions of the heavenly bodies, timing of eclipses, etc. "Judicial astrologers" study the supposed correlations between the positions of various celestial objects and the affairs of human beings.

The history of astrology in Europe and the Middle East are inextricably linked, with each region contributing to astrologial theories and continually influencing each other over time. Bouché-Leclercq, Cumont and Boll hold that the middle of the 4th century B.C. is when Babylonian astrology began to firmly enter western culture.
This spread of astrology was concomitant with the rise of a genuine scientific phase of astronomy in Babylonia itself. This may have weakened to some extent the hold that astrology had on the priests and the people. Another factor leading to the decline of the old faith in the Euphrates Valley may have been the advent of the Persians, who brought with them a religion which differed markedly from the Babylonian-Assyrian polytheism (see Zoroastrianism).
The spread of astrology beyond Babylonia is thus concomitant with the rise of a truly scientific astronomy in Babylonia itself, which in turn is due to the intellectual impulse afforded by the contact with new forms of culture from both the East and the West. In the hands of the Greeks and of the Egyptians both astrology and astronomy were carried far beyond the limits attained by the Babylonians.

Babylonia

Main article: Babylonian astrology
The history of astrology can now be traced back to ancient Babylonia, and indeed to the earliest phases of Babylonian history, in the third millennium B.C.
In Babylonia as well as in Assyria as a direct offshoot of Sumerian culture (or in general the "Mesopotamian" culture), astrology takes its place in the official cult 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 liver of the sacrificial animal (see omen).
The earliest extant Babylonian astrology text is the Enuma Anu Enlil (literally meaning "When the gods Anu and Enlil..."), dating back to 1600 B.C. This text describes various astronomical omens and their application to national and political affairs. For example, a segment of the text says: "If in Nisannu the sunrise appears sprinkled with blood, battles [follow]." Nisannu is the Babylonian month corresponding to March/April in the Western calendar.

Theory of Divine government

Just as the sacrificial method of divination rested on a well-defined theory - to wit, that the liver was the seat of the soul of the animal and that the deity in accepting the sacrifice identified himself with the animal, whose "soul" was thus placed in complete accord with that of the god and therefore reflected the mind and will of the god - so astrology is sometimes purported to be based on a theory of divine government of the world.
Starting with the indisputable fact that man's life and happiness are largely dependent upon phenomena in the heavens, that the fertility of the soil is dependent upon the sun shining in the heavens as well as upon the rains that come from heaven; and that, on the other hand, the mischief and damage done by storms and floods (both of which the Euphratean Valley was almost regularly subject to), were to be traced likewise to the heavens - the conclusion was drawn that all the great gods had their seats in the heavens.
In that early age of culture known as the "nomadic" stage, which under normal conditions precedes the "agricultural" stage, the moon cult is even more prominent than sun worship, and with the moon and sun cults thus furnished by the "popular" faith, it was a natural step for the priests, who correspond to the "scientists" of a later day, to perfect a theory of a complete accord between phenomena observed in the heavens and occurrences on earth.

Gods and planets

Of the planets five were recognized - Jupiter, Venus, Saturn, Mercury and Mars - to name them in the order in which they appear in the older cuneiform literature; in later texts Mercury and Saturn change places.
These five planets were identified with the gods of the Babylonian pantheon as follows:
Jupiter with Marduk;
Venus with the goddess Ishtar,
Saturn with Ninurta (Ninib),
Mercury with Nabu (Nebo),
and Mars with Nergal.
The movements of the sun, moon and five planets were regarded as representing the activity of the five gods in question, together with the moon-god Sin and the sun-god Shamash, in preparing the occurrences on earth. If, therefore, one could correctly read and interpret the activity of these powers, one knew what the gods were aiming to bring about.
The influence of Babylonian planetary lore appears also in the assignment of the days of the week to the planets, for example Sunday, assigned to the sun, and Saturday, the day of Saturn.

System of interpretation
The Babylonian priests accordingly applied themselves to the task of perfecting a system of interpretation of the phenomena to be observed in the heavens, and it was natural that the system was extended from the moon, sun and five planets to the more prominent and recognizable fixed stars.
The interpretations themselves were based (as in the case of divination through the liver) chiefly on two factors:
On the recollection or on written records of what in the past had taken place when the phenomenon or phenomena in question had been observed, and
Association of ideas - involving sometimes merely a play upon words - in connection with the phenomenon or phenomena observed.
Thus, if on a certain occasion, the rise of the new moon in a cloudy sky was followed by victory over an enemy or by abundant rain, the sign in question was thus proved to be a favourable one and its recurrence would thenceforth be regarded as a omen for good fortune of some kind to follow. On the other hand, the appearance of the new moon earlier than was expected was regarded as unfavourable, as it was believed that anything appearing prematurely suggested an unfavourable occurrence.
In this way a mass of traditional interpretation of all kinds of observed phenomena was gathered, and once gathered became a guide to the priests for all times.

Limitations of early knowledge
Astrology in its earliest stage was marked by three characteristics:
In the first place, In Babylonia and Assyria the interpretation of the movements and position of the heavenly bodies were centred largely and indeed almost exclusively in the public welfare and the person of the king, because upon his well-being and favour with the gods the fortunes of the country were dependent. The ordinary individual's interests were not in any way involved, and many centuries had to pass beyond the confines of Babylonia and Assyria before that phase is reached, which in medieval and modern astrology is almost exclusively dwelt upon - the individual horoscope.
In the second place, the astronomical knowledge presupposed and accompanying early Babylonian astrology was, though essentially of an empirical character, limited and flawed. The theory of the ecliptic as representing the course of the sun through the year, divided among twelve constellations with a measurement of 30° to each division, is of Babylonian origin, as has now been definitely proved; but it does not appear to have been perfected until after the fall of the Babylonian empire in 539 B.C. The defectiveness of early Babylonian astronomy may be gathered from the fact that as late as the 6th century B.C. an error of almost an entire month was made by the Babylonian astronomers in the attempt to determine through calculation the beginning of a certain year. For a long time the rise of any serious study of astronomy did not go beyond what was needed for the purely practical purposes that the priests as "inspectors" of the heavens (as they were also the "inspectors" of the sacrificial livers) had in mind.
In the third place, we have, probably as early as the days of Khammurabi, i.e. c. 2000 B.C., the combinations of prominent groups of stars with outlines of pictures fantastically put together, but there is no evidence that prior to 700 B.C. more than a number of the constellations of our zodiac had become part of the current astronomy.