What major earthly consequences were comets historically tied to portending?

Answer

Misfortune, death, or the downfall of rulers.

Historically, comets carried significant negative connotations due to their unpredictable and swift passage across the heavens. In many ancient societies, disturbances in the celestial order were interpreted as warnings of corresponding earthly disorder. This led to the strong cultural precedent that seeing a comet signaled impending misfortune, the death of important figures, or even the collapse of a ruling reign. The very nature of their swift, uninvited arrival reinforced this association with ill omen and major negative events affecting the earthly domain, especially the fate of monarchs.

What major earthly consequences were comets historically tied to portending?
astronomycometomensightings