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.
Pavia
It was at Pavia in 476 AD that the reign of Romulus Augustulus (r. 475-476), the last emperor of the Western Roman Empire ended and Roman rule ceased in Italy. Romulus Augustulus, while considered the last emperor of the Western Roman Empire, was actually a usurper of the imperial throne; his father Flavius Orestes having dethroned the previous emperor, Julius Nepos, and raised the young Romulus Augustulus to the imperial throne at Ravenna in 475. Though being the emperor, Romulus Augustulus was simply the mouthpiece for his father Orestes, who was the person who actually exercised power and governed Italy during Romulus Augustulus's short reign. Ten months after Romulus Augustulus's reign began, Orestes's soldiers under the command of one of his officers named Odoacer, rebelled and killed Orestes in the city of Pavia in 476. The rioting that took place as part of Odoacer's uprising against Orestes sparked fires that burnt much of Pavia to the point that Odoacer, as the new king of Italy, had to suspend the taxes for the city for five years so that it could finance its recovery. Without his father, Romulus Augustulus was powerless. Instead of killing Romulus Augustulus, Odoacer pensioned him off at 6,000 solidi a year before declaring the end of the Western Roman Empire and himself king of the new Kingdom of Italy.