What's the oldest written language in the world?
And the answer: Sumerian.
Sumerian is the oldest written language in existence. Dating back 5,000 years, it was the language of the people of Sumer in ancient Mesopotamia, which was located in what is now Iraq. At the time, people would write on wet clay tablets with a sharp object, and the tablets were then baked or left in the sun to harden.
Sumerian has been traced back to 3100 BCE in Mesopotamia, and was primarily used to conduct business. While it is recognized as the oldest written language today, Archaic Sumerian continues to be difficult to interpret and is poorly understood — since it was in use some 5,000 years ago, many resources have been lost to time.
The Classical period of the Sumerian language lasted from around 2500 to 2300 BCE. Much of our knowledge of the transactions made during this time come again from business, royal inscription, and even letters (both private and public). Although the Akkadian invasion of Babylonia set the language back, the records from this time period are extensive enough to construct more of an understanding of Sumerian grammar and vocabulary. Sumerian continued to be spoken and written up until the Babylonian identity took shape, at which point the last of the Sumerian written language was written in cuneiform.
However, the Sumerian language was lost around 4-6 BCE. A lack of information on early Sumerians meant that ancient historians had no means of understanding the role that Sumer held in early civilizations, and no means to decipher cuneiform. In the early 19th century, early decipherment of cuneiform led scholars to a novel realization: by creating better understanding the texts written in Babylonian, there emerged a newfound understanding of texts written in a language different from Babylonian. Ultimately, it was determined to be early Sumerian.