History of Europe
In 395 Theodosius I, who had made Christianity the official religion of the Roman Empire, would be the last emperor to preside over a united Roman Empire. The empire was split into two halves: the Western Roman Empire centred in Ravenna, and the Eastern Roman Empire (later to be referred to as the Byzantine Empire) centred in Constantinople. The Roman Empire was repeatedly attacked by Hunnic, Germanic, Slavic and other “barbarian” tribes (see: Migration Period), and in 476 finally the Western part fell to the Heruli chieftain Odoacer.
Western Roman Empire
The authority of Julius Nepos as Emperor was accepted not only by Odoacer in Italy, but by the Eastern Empire and Syagrius in Gaul (who had not recognized Romulus Augustulus). Nepos was murdered by his own soldiers in 480, a plot some attribute to Odoacer or the previous, deposed emperor Glycerius, and the Eastern Emperor Zeno chose not to appoint a new western emperor. Zeno, recognizing that no true Roman control remained over the territories legally governed by the Western court, instead chose to abolish the juridical division of the position of Emperor and declared himself the sole emperor of the Roman Empire. Zeno became the first sole Roman emperor since the division after Theodosius I, 85 years prior, and the position would never again be divided. As such, the (eastern) Roman emperors after 480 are the successors of the western ones, albeit only in a juridical sense. These emperors would continue to rule the Roman Empire until the Fall of Constantinople in 1453, nearly a thousand years later. As 480 marks the end of the juridical division of the empire into two separate imperial courts, some historians refer to the death of Nepos and abolition of the Western Empire by Zeno as the end of the Western Roman Empire.