Babylonian astrology led the way to Greek and Roman astrology. By the 6th century B.C. all the ancient civilizations were dying. In 650 B.C. Egypt had been conquered by the Assyrians. In 612 B.C. the Assyrians themselves were destroyed in a siege by the Medes and the Chaldean-Babylonians.
In 586 B.C. the Babylonians under Emperor Nebuchadnezzar II, destroyed the Temple of Solomon in Jerusalem and forced the Jews at the beginning of the triple conjunction of Uranus and Neptune and Pluto (UR=3⁰Aries | NE=23⁰ Aries | Pluto 0⁰ Taurus) to move to the city of Babylon.
Babylon became known as Chaldea. The Babylonian astrologers who had preserved the ancient teachings of Sumer were called Chaldeans, also Sabians.
Babylon was then conquered by Cyrus the Great, a Persian emperor (532 B.C.). Alexander the Great then conquered Persia, including Babylon, and conquered Egypt, in North Africa, along with all the nations in Asia Minor and all the nations in Asia. After his death, this area became the Seleucid Empire.
Following Alexander’s conquests, the Greeks went to study both in the East, in Babylon, and in the South, in Egypt. Both Sumer and Egypt and ancient Israel laid the quiet but firm foundations for the Judeo-Christian heritage.
All of the ancient Semitic races who had inherited the Sumerian learning themselves began to die out. The ancient knowledge was disappearing. In the 3rd, 2nd and 1st centuries B.C., Babylon became the last repository of the Sumerian civilization. By this time, the library of Ashurbanipal, still intact because it was on clay tablets, was buried under rubble and would remain lost for more than two thousand years.
The Greeks arrived in Babylon just in time to retrieve these Sumerian teachings.
Later, perhaps only a century or so before Babylon was finally and completely destroyed by the Persians in the 1st century B.C., Babylonian astrologers came west. Out of all the Babylonian astrologers who lived and practiced for millennia, these travelers are the ones remembered in history, because they transmitted their knowledge and wisdom to the Greek and Roman world.
Berosus was one of these Western émigrés. He was a priest of a Babylonian god called Bel. Berosus established himself on the island of Cos in the Aegean Sea around 280 B.C. (Franz Cumont, Astrology and Religion Among the Greeks and Romans. (New York: Dover Pubications. 1960 ed.: Orig. pub. In 1912, P. 33) Using the wisdom from those ancient clay tablets, copies of which he may have brought with him, he transmitted the ancient wisdom of Sumer to those curious Greek scientists. Another Babylonian, Soudines, is said to have taught the same lore; he lived about 238 B.C. (Cumont, page 33)
The Greeks learned all the Sumerian astrology that the Babylonians could teach them. Then they improved it.