As early as 5000 B.C.E., settlers began living on the high plateaus of Aryan. Located between the steppes of Asia and the Fertile Crescent were two deserts, which were rimmed by fertile plateaus. To the north were high mountains leading into Asia.

The lower ranges of mountains bordered present-day Afghanistan and Pakistan. On the western side loomed the Zagros Mountains and to the north were the rugged Elburz Mountains. The land consisted of dry basins of salt and sand, some marshlands, high volcanic mountain chains, and narrow coastal plains.

The climate was a combination of long, hot summers and cold, rainy winters with the mountainous regions of the north and west being subtropical. Temperatures and rainfall or snowfall varied with mountainous elevations, as winds brought moisture from the Persian Gulf. The Caspian region might receive more than 40 inches (102 cm) of rain each year. Average annual rainfall was only about

5 inches (12.7 cm) along the coastal plains and central portion of the plateau, with temperatures reaching as high as 120° F (49° C).Despite the harsh landscape, the early settlers harnessed the water from the rivers and snow that ran off the mountains in the spring. Persians began to build canals and ditches to bring precious water to their fields.

In these fertile areas, nomads found a perfect place for growing crops such as wheat and barley. They soon domesticated wild animals such as cattle and sheep and began to settle in communities.This region eventually became the bridge between the developing eastern and western civilizations of Mesopotamia and Egypt.

The rich plateaus attracted waves of nomadic tribes. During 1000 B.C.E., two Aryan tribes moved from the north and settled in the area. The Medes made their homes in the Zagros Mountains, with their rich mineral deposits of gold, silver, and semiprecious stones.

In ancient times, this area became known as Lydia. The Medes are remembered in history for creating the first coins to be used in trade. The second tribe moved near the edge of the Tigris River valley in an old kingdom called Elam and Pars, to form the Persia of ancient times.