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.
History of Rome
In 480, the last Western Roman emperor, Julius Nepos, was murdered and a Roman general of barbarian origin, Odoacer, declared allegiance to Eastern Roman emperor Zeno. Despite owing nominal allegiance to Constantinople, Odoacer and later the Ostrogoths continued, like the last emperors, to rule Italy as a virtually independent realm from Ravenna. Meanwhile, the Senate, even though long since stripped of wider powers, continued to administer Rome itself, with the Pope usually coming from a senatorial family. This situation continued until Theodahad murdered Amalasuntha, a pro-imperial Gothic queen, and usurped the power in 535. The Eastern Roman emperor, Justinian I (reigned 527–565), used this as a pretext to send forces to Italy under his famed general Belisarius, recapturing the city next year. The Byzantines successfully defended the city in a year-long siege, and eventually took Ravenna.