After the first three words, I assumed you were going to point out that the entire planet gets much hotter and colder as the zodiac shifts each year. The rising and setting of the sun has a similarly large effect, and the moon is also connected with tides.

Historical astrology was the precursor to modern astronomy, and was highly complex. There was likely a relatively strong tie to the course of history. If an astrological event associated with regime changes occurs, people are much more likely to revolt, because they are much less worried about being punished for a failed revolt.