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.
Orestes (5th century general)
In 475, Orestes was appointed "magister militum" and "patricius" by Western Roman Emperor Julius Nepos. This proved to be a mistake on the part of Nepos. By August 28, 475, Orestes, at the head of the "foederati" levies, managed to take control of the government in Ravenna, which had been the de facto capital of the Western Roman Empire since 402. Julius Nepos fled without a fight to Dalmatia, where he would continue to reign until his assassination in 480. With the emperor far away, Orestes elevated his son Romulus to the rank of "Augustus", so that the last Western Roman emperor is known as Romulus Augustulus meaning "little Augustus" as the emperor was only a 15-year-old boy at the time he became emperor in 475.