Hellenism is defined as the culture, ideals, and pattern of life of ancient Greece during classical times. Around the beginning of the 1st century B.C, in the Mediterranean region, a new form of astrology viz. horoscopic astrology was founded which came to be popularly known as Hellenistic astrology. The origin of Hellenistic astrology can be seen in ancient Egypt and Mesopotamia. Between 5th and the 15th century, the Hellenistic astrology had its influence on many other traditions of astrology in Middle East, India, Africa and Europe.
Although the Hellenistic period came to an end in the early part of the 1st century A.D, Hellenistic essentially its original forms until the 6th or 7th century A.D. Before this period, astrology was confined to observations and examinations constellations, planets, and natural phenomena associated with them, type of astrology was practiced world of the celestial bodies such as fixed which were believed to omens that might affect kings and kingdoms, as these celestial elements were thought of as Gods or their direct subordinates. Individuals other than kings and rulers did find no succour from primitive astrology
After Alexander the great invaded and conquered Persia during 330-330 B.C. Hellenistic kingdoms were established throughout south-west Asia and north-east Africa. It paved way to the entry of Greek culture and language into these new realms and large number of Greek colonies started creeping in. Different cultures came under one rule for the first time. In spite of the fact that these people belonged to different sects, the Babylonian tradition and culture were predominant in the entire kingdom. The differences in culture such as astrological, astronomical and philosophical, amongst Egypt, Babylonia and Persia came to a state of fusion which led to the blend of the systems of astrology of these regions.
Alexandria, one of the largest cities in Egypt, became the center of all these multi-cultural activities. Despite this fact the indigenous cultures too were equally given importance in view of the benefits, necessity and convenience they could derive from this. Persians were of the belief that the soul comes from the stars in the heavens. This belief and their mathematical skill in calculating the planetary motions played a key role in the transformation of omen astrology of the preceding millennium into a different type, the horoscopic astrology of the Hellenistic period. Greek philosophy and Egyptian astronomy played a vital role in revolutionizing the then prevailing forms to blossom into a different kind. Unlike the primitive astrology, the Hellenistic astrology has made a significant contribution by tracing individual horoscopes from the positions of the stars and planets on the date and time of one's birth. This is a very vital development in the history of astrology. The improvement in this direction interested other regions like Europe, India and the Middle East and soon spread to other nations also.
Ancient Babylonians began to compile and their system of astrology of celestial omens around the middle of 2000 B.C.Much of the astrological traditions that later developed in Asia, Europe and the Middle East originated from Ancient Babylonia. Babylonians have played a key role in spreading this system to China and Greece where it merged with the systems that existed there. In the middle of 4th century B.C Babylonian astrology found a way into Greece. Late 2nd or early 1st century was the time it blended with the Decanic astrology of ancient Egypt to develop into horoscopic astrology.
The use of the ascendant was employed along with the twelve celestial houses that were derived from it. The ascendant is known, in Greek, as horoskopos ("hour marker") and after this the system came to be known as horoscopic astrology. As a shift from the traditional way, drawing up of natal chart (astrological chart of an individual for the date and time of his birth) according to the position of the planets and stars came into practice which is considered as a significant contribution of Hellenistic astrology. This new form quickly spread across the ancient world into Europe, and the Middle East.
Ptolemy a mathematician, astronomer, geographer, astrologer and a poet who lived in Egypt under Roman rule, has contributed heavily for the advancement of astrology. Ptolemy is considered as the father of modern Western astrology. Western astrology arose out of the astrological writings of Ptolemy. "Tetrabiblos", developed by Ptolemy is the most important surviving ancient texts on Astrology. Even though his hypothesis that the Earth stood fixed at the center of the universe, with Sun, moon and the other planets whirling around it was disproved, this theory is still followed for the calculations of positions of the celestial bodies. Ptolemy systematized the study of planets, stars, houses as well as the signs of the zodiac.
The manner in which Ptolemy set the functions of each of these elements is being followed as a set of rules even now. He invented tropical zodiac which is a zodiac of signs marked by the vernal equinox. This solved the problem of precession and the occurrence of two zodiacs viz. the zodiac of constellations and the zodiac of signs.He bears the credit for propounding the geocentric theory that prevailed for over 1400 years. Universal astrology, Natal astrology and Katarchic astrology are the three major subdivisions of Hellenistic astrology which have been explained below: The scope of Universal astrology is aimed at groups of people who would be predictably affected by large scale natural calamities such as earthquakes, floods, famines etc. It dealt with health related calamities too and manmade disasters like wars were also under the purview of this division. Natal astrology is meant to create a birth chart of an individual using his date and time of birth and to examine charts to find out information about the person's life and fate. This will determine not only their personality traits, but also the paths they will take in life.
The final subdivision, Katarchic astrology is aimed at helping individuals know the best date and time to perform auspicious events such as weddings, naming, start a business etc., according to their birth chart. It uses event astrology as well, to furnish all the details of a particular event. Hellenistic astrology is considered as the ancestor of many of the modern traditions of astrology that still flourish all around the world today. The importance of the Hellenistic astrology is felt only recently and steps are on for recovery and reconstruction. Many a scholar and astrological community are working in this line to accomplish the complete recovery of this tradition.