Light in the Dark Ages By Mnielsen27 Period: 400 to 423 Honorius - Western Empire 410 Visigoths sack Rome under King Alaric 418 Frank takes Gaul Period: 423 to 440 - 430 St. Augustine dies 431 Council of Ephesus - third Ecumenical - defined Mary to be the Mother of God Period: 440 to 460 St. Leo I 445 Emp. Valentinian III acknowledges papal supremacy 451 Council of Chalcedon - fourth Ecumenical defined the human and divine natures of Christ in one person 452 St. Leo I (the great) meets Attila the Hun Period: 461 to 474 - Period: 474 to 491 Zeno - Eastern Emp. 476 End of Roman Empire, last western explorer is Romulus Augustulus Period: 491 to 539 - 493 Theodoric the Ostrogoth becomes king of Italy Period: 539 to 565 Justinian - East. Emp.