Holy Roman Empire
The empire was dissolved on 6 August 1806, when the last Holy Roman Emperor Francis II (from 1804, Emperor Francis I of Austria) abdicated, following a military defeat by the French under Napoleon at Austerlitz (see Treaty of Pressburg). Napoleon reorganized much of the Empire into the Confederation of the Rhine, a French satellite. Francis' House of Habsburg-Lorraine survived the demise of the empire, continuing to reign as Emperors of Austria and Kings of Hungary until the Habsburg empire's final dissolution in 1918 in the aftermath of World War I.
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.