Heraclius

Heraclius was one of the most heroic and tragic figures on the Byzantine imperial throne. The son of the Exarch of Carthage, Heraclius sailed to Constantinople in 610 CE to overthrow the tyrant Phocas, inheriting an empire facing total annihilation. Sasanian Persian armies had overrun Syria, Palestine, and Egypt, carrying off the True Cross from Jerusalem and marching to the gates of Chalcedon directly across the Bosporus from Constantinople.

Borrowing gold from the Church to melt down into coin, Heraclius reorganized Byzantine military provinces into self-sustaining military districts called Themes. In an audacious counter-offensive worthy of Alexander the Great, Heraclius sailed into the Black Sea, marched deep into the Persian heartland, and shattered King Khosrow II's elite forces at the Battle of Nineveh in 627 CE. In 630 CE, he entered Jerusalem in triumphant barefoot pilgrimage to restore the True Cross to the Church of the Holy Sepulchre. He changed the official language of the empire from Latin to Greek, adopting the imperial title Basileus. Exhausted by three decades of warfare, his final years were shadowed by the sudden emergence of the Arab Muslim conquests.