Iran’s history as a nation of people speaking an Indo-European language did not begin until the middle of the second millennium B.C. Before then, Iran was occupied by peoples with a variety of cultures. There are numerous artifacts attesting to settled agriculture, permanent sun-dried- brick dwellings, and pottery-making from the sixth millennium B.C. The most advanced area technologically was ancient Susiana, present-day Khuzestan Province. By the fourth millennium, the inhabitants of Susiana, the Elamites, were using semipictographic writing, probably learned from the highly advanced civilization of Sumer in Mesopotamia (ancient name for much of the area now known as Iraq), to the west.