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 the Roman Empire
After 395, the emperors in the Western Roman Empire were usually figureheads, while the actual rulers were military strongmen who took the title of "magister militum", "patrician" or both—Stilicho from 395 to 408, Constantius from about 411 to 421, Aëtius from 433 to 454 and Ricimer from about 457 to 472. The year 476 is generally accepted as the formal end of the Western Roman Empire. That year, Orestes, having stolen power from the emperor Julius Nepos the year before, refused the request of Germanic mercenaries in his service for lands in Italy. The dissatisfied mercenaries, including the Heruli, revolted. The revolt was led by the Germanic chieftain Odoacer. Odoacer and his men captured and executed Orestes; weeks later they captured Ravenna and deposed Orestes' usurper son, Romulus Augustus. This event has been traditionally considered the fall of the Roman Empire in the West. Odoacer quickly conquered the remaining provinces of Italy.