The ancient society that used cuneiform as a system of writing is the Sumerians, who lived in ancient Mesopotamia. Cuneiform is one of the earliest forms of writing, originating around 3400 BCE. It used a series of wedge-shaped marks inscribed on clay tablets, and it served various purposes including record-keeping, literature, and legal documentation. This writing system laid the foundation for subsequent forms of writing and is crucial for understanding the cultural and administrative complexities of early civilizations.