Sumer
Sumer () is the earliest known civilization in the historical region of southern Mesopotamia, modern-day southern Iraq, during the Chalcolithic and Early Bronze ages, and one of the first civilizations in the world along with Ancient Egypt and the Indus Valley. Living along the valleys of the Tigris and Euphrates, Sumerian farmers were able to grow an abundance of grain and other crops, the surplus of which enabled them to settle in one place. Prehistoric proto-writing dates back before 3000 BC. The earliest texts, from c. 3300 BC, come from the cities of Uruk and Jemdet Nasr; early cuneiform script emerged around 3000 BC.
Ostracon
In October 2008, Israeli archaeologist, Yosef Garfinkel of the Hebrew University of Jerusalem, has discovered what he says to be the earliest known Hebrew text. This text was written on an Ostracon shard; Garfinkel believes this shard dates to the time of King David from the Old Testament, about 3,000 years ago. Carbon dating of the Ostracon and analysis of the pottery have dated the inscription to be about 1,000 years older than the Dead Sea Scrolls. The inscription has yet to be deciphered, however, some words, such as king, slave and judge have been translated. 
The shard was found about 20 miles southwest of Jerusalem at the Elah Fortress in Khirbet Qeiyafa, the earliest known fortified city of the biblical period of Israel.