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.
Proto-Sinaitic script
The term Proto-Canaanite is also used when referring to the ancestor of the Phoenician or Paleo-Hebrew script, respectively, before some cut-off date, typically 1050 BC, with an undefined affinity to Proto-Sinaitic. 
While no extant inscription in the Phoenician alphabet is older than c. 1050 BC, "Proto-Canaanite" is a term used for the early alphabets as used during the 13th and 12th centuries BC in Phoenicia. However, the Phoenician, Hebrew, and other Canaanite dialects were largely indistinguishable before the 11th century BC. A possible example of "Proto-Canaanite" was found in 2012, the Ophel inscription, when during the excavations of the south wall of the Temple Mount by the Israeli archaeologist Eilat Mazar in Jerusalem on a storage jar made of pottery. Inscribed on the pot are some big letters about an inch high of which only five are complete and traces of perhaps three additional letters written in Proto-Canaanite script.