There are many discussion and disagreement between researchers especially linguistics and historians about what the religion and ethic of Achaemenid kings were, specifically those who were the first kings of this dynasty. Some of them believe they were Zoroastrian, some others disagree and others choose Indo-Iranian religion. Generally, everything they declare is based on historical evidence or linguistic implications and it seems nobody considers the existing content and concept of Achaemenid inscriptions and compares them based on religious scholarship or the doctrine of Zoroastrian religion nonetheless the Achaemenid’s main and frequency slogan which Dariush left behind on inscriptions to reinforce his legitimacy and introduces earth, sky, people and happiness as creations of Ahuramazda is profoundly based on Zoroastrianism.
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