The Achaemenid king who seized the Persian throne in 522 BCE amid a violent succession crisis and then reorganized the largest empire the world had yet seen -- dividing it into provinces with fixed tribute, standardizing coinage, building the Royal Road and the ceremonial capital at Persepolis -- while leaving a cliff-carved inscription that is both his official self-defense and a key that later unlocked cuneiform.
High on a cliff in western Iran, far above any road, Darius had workers carve his story into rock in three languages. It shows him with his foot on a fallen man, telling how he killed a usurper and, in a single year, fought nineteen battles and took nine rebel kings. The carving was meant to be read by gods more than by people, since no one on the ground could reach it. Centuries later it became something its author never imagined: the key that let scholars finally read the lost writing of the ancient Near East.