Darius the Mede is mentioned in Dan. (e.g. 5: 31) as ruling after Belshazzar and before Cyrus, but there is no other evidence for such a monarch.

Darius I (522–486 BCE) is the Persian ruler who confirmed the edict permitting the rebuilding of the Temple in 520–515 BCE (Ezra 5 and 6). In classical history of Greece he is famous for his defeat at Marathon in 490 BCE. His palace was at Susa.