The death of Constantine the Great, Emperor of the Roman Empire from 306 to 337, left the Empire with a new capital in the east at Constantinople and with three critical challenges, any one of which could have caused its collapse.

The first was civil war as Constantine's three sons fought among themselves for his throne--a struggle from which Constantius II finally emerged in 350 not necessarily as victor but as last-man-standing. In any event, leadership of the Empire was unified once more.

The second challenge, the military threat from Persia in the east, though not resolved was at least contained by a disadvantageous peace treaty. In the west, however, the cloud of territorial encroachment by the Goths from the north grew steadily darker, a trend underscored by a great Goth victory in the Battle of Adrianople in 378. As Emperor from 379, Theodosius the Great brought a temporary respite through a careful policy of appeasing and containing the Goths.

Theodosius' death in 495 brought the Empire into the less skilled hands of his sons Honorius and Arcadius, who compounded their lack of statecraft by their deep personal animosity. Their personal hostility was resolved by a decision to divide the Empire irrevocably into two parts. Arcadius became Emperor of the Eastern Empire, which soon became known as the Byzantine Empire. Honorius assumed the throne of the new Western Empire--just 81 years before its demise at the hands of Odoacer, leader of its rebellious barbarian mercenaries.