The Austrian Empire (initially the Holy Roman Empire) was ruled throughout the period by the Habsburg Emperor Francis II (1768-1835) who succeeded Leopold II in 1792. On August 11th 1804, he assumed the title of Emperor Francis I of Austria, and following the defeat of 1805 the Holy Roman Empire was officially disolved and the title renounced on August 6th 1806.
The Empire spread from Italy to the Netherlands and from Poland to the Balkans, incorporating in 1793 some 6,500,000 Germans, 3,600,000 Czechs, 2,000,000 Walloons and Flemms, 1,000,000 Poles, 900,000 Croats and 700,000 Serbs and numerous smaller nationalities. The Emperor ruled Austria as Emperor, but the 'Hungarian' possesions (including Transylvania) as King of Hungary; thus the Empire's multi-national army was styled the Kaiserlich-konigliche Armee ('Imperial and Royal Army'). The central administration ruled the 'German' parts of the Empire; Hungary was ruled by its own 'Diet' (parliament) which enjoyed a degree of independence, as did the Netherlands, Italian duchies and the Tyrol. Foreign policy, like other aspects of government, was nominally decided by the Emperor, but later in the period enormous influence was exercised by the foreign minister, Count (later Prince) Clemens Wenzel Lothar Metternich-Winneburg (1793-1859). He first supported an alliance with France, helping to arrange a diplomatic marriage between Napoleon and the Emperor's daughter Marie-Louise, but after the 1812 campaign, he realized that Napoleon was doomed and took Austria into the war against France.
Metternich's influence at the Congress of Vienna was profound, and he became not only the leading statesman in Europe but virtual ruler of the Empire until he was undone by the 'year of revolutions' (1848), the liberal political thought that he had attempted to suppress. Military affairs were run by a combined civil-military council, the Hofkriegstrat, which issued a vast amount of unnecessary and burdensome directives. Despite the efforts of such great leaders and reformists as Archduke Charles, (Napoleon's most enduring enemy) the Empire lost territory progressively through the Revolutionary wars and Napoleonic Wars, each defeat costing land; the Austrian-Netherlands went by the Treaty of Campo Formio (1797), though Austria gained Venice by consolation; the Italian duchies were taken by conquest, Venice and the Tyrol went by the Treaty of Pressburg (1806), and the Treaty of Schonbrunn (1809) completed the humiliation of the Empire. Despite such defeats, Austria remained Napoleon's most persistent continental adversary, and not even defeats of the magnitude of Marengo, Ulm, Austerlitz and Wagram caused a total abandonment of the fight. After a brief period of service under the French direction (the 'Reserve Corps' for the 1812 Russian campaign), in 1813-14 Austria played a leading part in the overthrow of Napoleon.