<Li> ^ Whilst the deposition of Romulus Augustulus in 476 is the most commonly cited end date for the Western Roman Empire, the last Western Roman Emperor Julius Nepos did not die until 480, when the title and notion of a separate Western Empire were actually abolished . Another suggested end date is the reorganization of Italy and abolition of separate Western Roman administrative institutions under Justinian during the latter half of the 6th century . </Li> <P> In historiography, the Western Roman Empire refers to the western provinces of the Roman Empire at any time during which they were administered by a separate independent Imperial court, coequal with that administering the eastern provinces, referred to as the Eastern Roman Empire . The terms "Western Roman Empire" and "Eastern Roman Empire" are modern inventions that describe political entities that were de facto independent . At no point did the Romans themselves consider the Empire to have been split into two separate Empires . They considered it remained a single state that was governed by two separate Imperial courts as an administrative expediency . A system of government of this kind is known as a diarchy . </P> <P> Though the Empire had seen periods with more than one Emperor ruling jointly before, the view that it was impossible for a single emperor to govern the entire Empire was established by Emperor Diocletian following the disastrous civil wars and disintegrations of the Crisis of the 3rd century . His ideas were instituted in Roman law by the introduction of the Tetrarchy in AD 286, which divided the position of Augustus (Emperor) into two; one in the East and one in the West, each with an appointed Caesar (junior Emperor and designated successor). Though the tetrarchic system would collapse in a matter of years, the East - West administrative division would endure in one form or another for centuries to come . As such, the Western Roman Empire would exist intermittently in several periods between the 3rd and 5th centuries . Though some emperors, such as Constantine I and Theodosius I, would manage to rise to the position of Augustus in both parts and as such reunify the Empire, it would often divide again upon their deaths . After the death of Theodosius I in AD 395, the Empire was divided between his sons and would not be reunified . Eighty - five years later, in 480, following various invasions and the collapse of central control in the West, Emperor Zeno of the Eastern Empire recognized the reality of the Western Empire's reduced domain . Effective central control had ceased to exist even in the Italian Peninsula after the depositions of Julius Nepos and Romulus Augustulus--and Zeno therefore abolished the Western court and proclaimed himself the sole emperor of the Roman Empire . </P> <P> The rise of Odoacer and his Germanic foederati to rule over Italy in 476 was popularized by the eighteenth - century historian Edward Gibbon as a demarcating event for the end of the Western Empire and is sometimes used to mark the transition from Antiquity to the Middle Ages . Odoacer's Italy, and other barbarian kingdoms, would maintain a pretense of Roman continuity through the continued use of the old Roman administrative systems and nominal subservience to the Eastern Roman court . Direct Imperial rule would be reimposed in large parts of the West, including the prosperous regions of North Africa and the ancient Roman heartland of Italy as well as parts of Hispania, in the sixth century by the armies of the Eastern Empire under Emperor Justinian I. Political upheaval in the Eastern heartlands, combined with foreign invasions and religious issues, made efforts to retain control of these territories difficult and they were gradually lost, this time for good . </P>

When did eastern and western roman empire split