Summary: assisted by other Gods, Darius the King emphasized the importance of righteousness in his reign, rewarding the good and punishing the wrongdoers. This commitment to justice and equitable governance was a fundamental principle of Achaemenian polity, laid down by Cyrus the Great in 539 B.C. Despite early Greek writers acknowledging this respect for Truth and Justice, a shift in policy occurred later as Iranian beliefs were organized into Zoroastrianism. This rigid religious identity, intertwined with militant Iranian imperialism, led to persecution of Manicheans and Christians. Yet, the foundational values of Iranianism, rooted in a fervent adoration of the god Ahura-Mazda, shaped Iranian culture and influenced neighboring civilizations, with mutual cultural exchanges between Iran and India, particularly evident in the realms of art, literature, science, and philosophy. This rich cultural interchange remained significant throughout history, representing a convergence of diverse traditions and beliefs amidst changing political landscapes.