Roman emperor
The Western Roman Empire collapsed in the late 5th century. Romulus Augustulus is often considered to be the last emperor of the West after his forced abdication in 476, although Julius Nepos maintained a claim recognized by the Eastern Empire to the title until his death in 480. Following Nepos' death, the Eastern Emperor Zeno abolished the division of the position and proclaimed himself as the sole Emperor of a reunited Roman Empire. The Eastern imperial lineage continued to rule from Constantinople ("New Rome"); they continued to style themselves as Emperor of the Romans (later βασιλεύς Ῥωμαίων in Greek), but are often referred to in modern scholarship as Byzantine emperors. Constantine XI Palaiologos was the last Roman emperor in Constantinople, dying in the Fall of Constantinople to the Ottomans in 1453.
Historiography of the fall of the Western Roman Empire
Gibbon took September 4, 476 as a convenient marker for the final dissolution of the Western Roman Empire, when Romulus Augustus, the last Emperor of the Western Roman Empire, was deposed by Odoacer, a Germanic chieftain. Some modern historians question the significance of the year 476 for its end. Julius Nepos, the Western emperor recognized by the Eastern Roman Empire, continued to rule in Dalmatia, until he was assassinated in 480. The Ostrogothic rulers of Italia considered themselves upholders of the direct line of Roman tradition, and the Eastern emperors considered themselves the sole rightful Roman rulers of a united empire. Roman cultural traditions continued throughout the territory of the Western Empire, and a recent school of interpretation argues that the great political changes can more accurately be described as a complex cultural transformation, rather than a fall.