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.
The title lasted just a little over one century until 1918, but it was never clear what territory constituted the "Empire of Austria". When Francis took the title in 1804, the Habsburg lands as a whole were dubbed the Kaisertum Österreich. Kaisertum might literally be translated as "emperordom" (on analogy with "kingdom") or "emperor-ship"; the term denotes specifically "the territory ruled by an emperor", and is thus somewhat more general than Reich, which in 1804 carried connotations of universal rule. Austria proper (as opposed to the complex of Habsburg lands as a whole) had been an Archduchy since the 15th century, and most of the other territories of the Empire had their own institutions and territorial history, although there were some attempts at centralization, especially during the reign of Marie Therese and her son Joseph II and then finalized in the early 19th century. When Hungary was given self-government in 1867, the non-Hungarian portions were called the Empire of Austria and were officially known as the "Kingdoms and Lands Represented in the Imperial Council (Reichsrat)". The title of Emperor of Austria and the associated Empire were both abolished at the end of the First World War in 1918, when German Austria became a republic and the other kingdoms and lands represented in the Imperial Council established their independence or adhesion to other states.
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