In the 4th century bc, astrology was passed from the Babylonians to Greeks. Even so, the origin of astrology in a primitive form is credited to the Chaldeans from as early as 3000 bc. As the influence from the heavenly bodies were observed, it was presumed that human life resided in the heavens, and up there a message might be read.
The Ptolemaic system is what the construction of the horoscope is based off. The sun, moon, and stars have effect on the signs and their positions. The houses were spaced perfectly into 12 sections of 30 degrees. The positions of the houses start with the vernal equinox proceeding eastward along the ecliptic. These placements and structures were more knowingly studied by the Egyptians, Hindus, Chinese, Etruscans, and the Chaldeans of Babylonians.
The signs were adopted from the Babylonians, later used by all believers in astrology. Once particular signs and houses have been established, mythological characteristics that were modified by geometrical relationships, are used to foretell events in the life. Many cultures used to base their life off their zodiac sign. That was until the spread of a religion occurred.