Which ancient civilization created a system of symbols representing spoken sounds?

The Phoenicians are recognized for developing one of the earliest systems of writing that represented spoken sounds through a set of symbols. This script was crucial because it moved away from using pictographs, which depicted the objects or ideas directly, to an alphabetic system where individual symbols corresponded to specific sounds. This innovation greatly influenced the development of writing systems in various cultures, including Greek and Latin alphabets, as it allowed for greater flexibility and ease in recording the spoken language.

The significance of the Phoenician alphabet lies in its simplicity and efficiency, making it easier for traders and communicators to convey information, which was especially vital for a civilization engaged in extensive maritime trade. As such, their writing system laid the foundational groundwork for modern alphabets used today. The other civilizations mentioned, while having their own writing systems, did not create a phonetic alphabet in the same way the Phoenicians did.