Persian culture traces some thousands of years from prehistoric mythic times to the present. In the course of this development from the settlement of Aryan tribes on the Iranian plateau, society developed from nomadic to settled, from religion of nature to the monotheism of Islam, and from tribal to modern representative government. The national epic chronicles the struggles of heroes from the coming of man’s use of fire and minerals, from philosophical teachings of Zoroaster, the tolerance of Cyrus and Alexander, and revival of learning. From ancient times, the concepts of Iranian morality based on triumph of good over evil and duty to right infringement of a just social order have predominated.