Writing
The invention of the first writing systems is roughly contemporary with the beginning of the Bronze Age of the late 4th millennium BC. The Sumerian archaic cuneiform script and the Egyptian hieroglyphs are generally considered the earliest writing systems, both emerging out of their ancestral proto-literate symbol systems from 3400 to 3200 BC with earliest coherent texts from about 2600 BC. It is generally agreed that Sumerian writing was an independent invention; however, it is debated whether Egyptian writing was developed completely independently of Sumerian, or was a case of cultural diffusion.
Cradle of civilization
The earliest traditional Chinese dynasty for which there is both archeological and written evidence is the Shang dynasty (1600 to 1046 BC). Shang sites have yielded the earliest known body of Chinese writing, the oracle bone script, mostly divinations inscribed on bones. These inscriptions provide critical insight into many topics from the politics, economy, and religious practices to the art and medicine of this early stage of Chinese civilization. Some historians argue that Erlitou should be considered an early phase of the Shang dynasty. The U.S. National Gallery of Art defines the Chinese Bronze Age as the period between about 2000 and 771 BC; a period that begins with the Erlitou culture and ends abruptly with the disintegration of Western Zhou rule. The Sanxingdui culture is another Chinese Bronze Age society, contemporaneous to the Shang dynasty, however they developed a different method of bronze-making from the Shang.