Excerpted and adapted from the book Divination: Sacred Tools for Reading the Mind of God by Paul O’Brien
Early Astrology was a marriage of astronomy and mythology. Several ancient cultures—including Mayan, Indian and Chinese—mastered astronomy to determine celestial events like solstices, equinoxes, moon cycles, seasons, and eclipses. They also used it to help interpret events or determine auspicious times for various activities. Astrological traditions from cultures other than our own have remained in continuous use since ancient times, including Vedic Astrology and the Mayan Calendar. Western Astrology as we know it is a descendant of Mesopotamian celestial observation and omen-reading that began around 2000 B.C.
According to archeological evidence, it is likely that there was a religious, as well as astronomical, significance to megalithic constructions such as Stonehenge and Easter Island built in various parts of the world from 4000 to 2000 B.C. Some historians assert that the mathematical sophistication of these early cultures was equal to that of Renaissance Europe, and that this knowledge was passed along to Mesopotamia around the same time as the development of star-based omen lore in 3000–2000 B.C.
There is little known about the practicing astrologers of these times, except that they also would have been astronomers, and that at least part of their divination practices involved interpreting patterns of events based on observable movements in the heavens.
In 538 B.C., Mesopotamia was conquered by the Persians, who contributed their greater mathematical sophistication to Mesopotamia’s astronomy. Humans were now able to calculate the paths of planets across the sky (or around the Earth, as was the understanding of the time), and develop horoscopes much like the ones we use today. The oldest natal horoscope ever found is dated April 29, 410 B.C.
Modern Astrology, including sun sign interpretation, was systematized by Ptolemy in his book Tetrabiblos during the second century A.D. Ptolemy synthesized much of the contemporary astrological thinking and arranged it into a consistent and unified body of work. Much of modern Western Astrology borrowed from Ptolemy’s work.
After the fall of the Roman Empire, Astrology was condemned and suppressed by the Church. It didn’t find a widespread following again until eighth century Spain during the wars with the Arabs, who had continued to use Astrology. The Emperor Charlemagne hired an astrologer and took up studies on the subject. Astrology was used by the ruling class throughout the European Reformation (fourteenth to seventeenth centuries), and then fell into disfavor until the Theosophical movement revived interest in the United States during the 1880s. Ironically, it was during this period of neglect by the ruling classes that Astrology became almost respectable among the general public, and this trend of interest in and use of Astrology is still increasing today.