Iranian society occupies a unique situation within the Middle East. The country fulfils the criteria of a recognizable human unit with a culture that has been distinctive for many centuries. Iran has a pronounced physiography. Human settlement in Iran is concentrated on the interior piedmont slopes of the north and west, and it extends through the outer Alburz piedmont to include the southern Caspian coastlands. Climatically, it is fundamentally part of the general Middle Eastern regime, as Iran has wider extremes than are experienced in many other countries of that region. Besides the settled communities there are important groups of nomads and semi-nomads in Iran. In recent times cupidity aroused by Iran's richness in petroleum made this richness a political liability rather than an asset. If we seek to define Iran's function as a state and as a human grouping in terms of a personality, then the country can be said to generate, to receive and transmogrify, and to re-transmit.