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.
Ancient Rome
The Roman noble and former emperor Julius Nepos continued to rule as emperor from Dalmatia even after the deposition of Romulus Augustus until his death in 480. Some historians consider him to be the last emperor of the Western Empire instead of Romulus Augustus.