Answer:
Darius I commonly known as Darius the Great, was a Persian ruler who served as the third King of Kings of the Achaemenid Empire, reigning from 522 BCE until his death in 486 BCE. Darius the Great was an Achaemenid ruler noted for his administrative genius, his great building projects, and his benevolence toward the diverse peoples under his sovereignty. His policies and building projects helped fortify his vast empire and enhance trade throughout. Darius was a member of the royal bodyguard of Cambyses II, the son and heir of Cyrus the Great who ruled for several years before dying mysteriously in 522. Later that same year, Darius took the throne after killing an alleged usurper he claimed had only pretended to be Cambyses’ brother Bardiya. Darius the Great helped unify the Achaemenid empire, which spanned a vast heterogeneous territory. Much of this unification was achieved through building upon the administrative reform program begun by Cyrus the Great to fit the needs of the expansive empire. It was also achieved through Darius’s encouragement and patronage of local traditions and building projects.
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