Darius I, known as Darius the Great, was one of the most powerful rulers of the
Achaemenid Empire and ruled from 522 to 486 BCE. He came to power after a period of political unrest and worked to strengthen and organize the vast empire. Darius divided the empire into administrative regions called satrapies, improved taxation systems, and built important infrastructure such as the
Royal Road to improve communication and trade. He also supported large construction projects, including the ceremonial capital at
Persepolis. During his reign the empire expanded and reached one of its greatest levels of power, although his military campaign against the Greek city-states ended in defeat at the
Battle of Marathon.
