Emperor
The first Austrian Emperor was the last Holy Roman Emperor Francis II. In the face of aggressions by Napoleon, Francis feared for the future of the Holy Roman Empire. He wished to maintain his and his family's Imperial status in the event that the Holy Roman Empire should be dissolved, as it indeed was in 1806 when an Austrian-led army suffered a humiliating defeat at the Battle of Austerlitz. After which, the victorious Napoleon proceeded to dismantle the old "Reich" by severing a good portion from the empire and turning it into a separate Confederation of the Rhine. With the size of his imperial realm significantly reduced, Francis II, "Holy Roman Emperor" became Francis I, "Emperor of Austria". The new imperial title may have sounded less prestigious than the old one, but Francis' dynasty continued to rule from Austria and a Habsburg monarch was still an emperor ("Kaiser"), and not just merely a king ("König"), in name.
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.