Archaeologists define the Proto-Elamite phenomenon by the appearance of Proto-Elamite writing, the first form of local writing in Iran on tablets in many cases together with specific types of other management tools and pottery, over a vast geographical territory across the Iranian plateau. Different explanations have been offered to account for this spread and the shift from a Mesopotamian-oriented culture during the earlier period (Late Uruk) to a predominantly Iranian-oriented culture during the late fourth and early third millennium BCE. However, up to now, most of these explanations have been concentrated on the recovered material culture from Fars in the southern part of the plateau and Khuzestan in the southwest. New discoveries from sites on the northern fringes of the plateau depict a fresh and more complete picture of this enigmatic phenomenon. The new excavations and surveys conducted in the settlements that contain the material culture of this horizon have significantly added to our knowledge about the formation and spreading processes of this horizon. Cultural material recently recovered from these sites have extended the Proto-Elamite territory even further, have changed our understanding of the relationships among them and the potential ways this cultural horizon was shaped and diffused. In this paper, we present some of the newly discovered evidence from these sites including but not limited to: Sofalin, Shoghali, Ozbaki, Gholi Darvish and compare them with our older understanding of the presence of this cultural horizon in the center and northern parts of the Iranian plateau.