The History of Persia

India was the oldest civilization, at least 10,000 years old. India spanned the entire Indian subcontinent, including Gandhara and present day Afghanistan. And there were Indianized kingdoms all across central Asia, including present day Tibet and present day so called Xinjiang of China. Iran itself was an Indianized civilization, which later acquired its own characteristics via Zoroastrianism. So if we take a 3000 year lens, you had three civilizations: India, China, and Persia.