Francis II, Holy Roman Emperor in the context of "Maria Leopoldina of Austria"

The Austrian Empire, officially known as the Empire of Austria, was a multinational European great power from 1804 to 1867, created by proclamation out of the realms of the Habsburgs. During its existence, it was the third most populous nation in Europe after the Russian Empire and the United Kingdom, while geographically, it was the third-largest empire in Europe after the Russian Empire and the First French Empire.

The empire was proclaimed by Francis II in 1804 in response to Napoleon's declaration of the First French Empire, unifying all Habsburg possessions under one central government. It remained part of the Holy Roman Empire until the latter's dissolution in 1806. It continued fighting against Napoleon throughout the Napoleonic Wars, except for a period between 1809 and 1813, when Austria was first allied with Napoleon during the invasion of Russia and later neutral during the first few weeks of the Sixth Coalition War. Austria and its allies emerged victorious in the war, leading to the Congress of Vienna, which reaffirmed the empire as one of the great powers of the 19th century.

The title of imperator (/ˌɪmpəˈrɑːtər/ im-pə-RAH-tər) originally meant the rough equivalent of commander under the Roman Republic. Later, it became a part of the titulature of the Roman Emperors as their praenomen. The Roman emperors generally based their authority on multiple titles and positions, rather than preferring any single title. Nevertheless, imperator was used relatively consistently as an element of a Roman ruler's title throughout the Principate and the later Roman Empire. It was abbreviated to "IMP" in inscriptions. The word derives from the stem of the verb imperare, meaning 'to order, to command'. The English word emperor derives from imperator via Old French: Empereür.

The Venetian Province (Venetian: Provinsa Veneta, German: Provinz Venedig) was the name of the territory of the former Republic of Venice ceded by the French First Republic to the Habsburg monarchy under the terms of the 1797 Treaty of Campo Formio that ended the War of the First Coalition. The province's capital was Venice.

In the course of the French Italian campaign of 1796–1797, the Signoria of Venice under Doge Ludovico Manin had rejected an alliance with the French, whereupon General Napoleon Bonaparte occupied the city on 14 May 1797, leading to the fall of the Republic of Venice and the establishment of the Provisional Municipality of Venice. In exchange for renouncing all rights to the Austrian Netherlands and recognizing the French Cisalpine Republic, Francis II, Holy Roman Emperor gained the conquered Venetian territory including the Dalmatian coast but not the smaller Ionian Islands, beyond.

The War of the Fifth Coalition was a European conflict in 1809 that was part of the Napoleonic Wars and the Coalition Wars. The main conflict took place in Central Europe between the Austrian Empire of Francis I and Napoleon's French Empire. The French were supported by their client states—the Kingdom of Italy, the Confederation of the Rhine and the Duchy of Warsaw. Austria was supported by the Fifth Coalition which included the United Kingdom, Portugal, Spain, and the Kingdoms of Sardinia and Sicily, although the latter two took no part in the fighting. By the start of 1809 much of the French army was committed to the Peninsular War against Britain, Spain and Portugal. After France withdrew 108,000 soldiers from Germany, Austria attacked France to seek the recovery of territories lost in the 1803–1806 War of the Third Coalition. The Austrians hoped Prussia would support them, having recently been defeated by France, but Prussia chose to remain neutral.

On 10 April 1809, Austrian forces under Archduke Charles crossed the border of Bavaria, a French client state. The French response, under Louis-Alexandre Berthier, was disorganised but order was imposed with the arrival of Napoleon on 17 April. Napoleon led an advance to Landshut, hoping to cut off the Austrian line of retreat and sweep into their rear. Charles crossed the Danube at Regensburg, which allowed him to retreat eastwards, although he failed to reach the Austrian capital, Vienna, before the French. A French assault across the Danube was repulsed on 21–22 May at the Battle of Aspern-Essling but a repeat attack was successful in July. Napoleon won a major victory at the 5–6 July Battle of Wagram, which forced the Austrians to sign the Armistice of Znaim on 12 July. Austrian invasions of the Duchy of Warsaw and Saxony (where they fought alongside the Black Brunswickers) were repulsed and they were driven out of their territories in Italy. British forces landed in Walcheren, in the French client state of Holland, but were unable to seize their objective of capturing Antwerp and later withdrew.

The Treaty of Chaumont was a series of separately-signed but identically-worded agreements in 1814 between the Austrian Empire, the Kingdom of Prussia, the Russian Empire and the United Kingdom. They were dated 1 March 1814, although the actual signings took place on 9 or 19 March. The treaty was intended to draw the powers of the Sixth Coalition into a closer alliance in case France rejected the peace terms they had recently offered. Each power agreed to put 150,000 soldiers in the field against France and to guarantee for twenty years the European peace (once obtained) against French aggression.

Following discussions in late February 1814, representatives of Austria, Prussia, Russia, and the United Kingdom reconvened a meeting at Chaumont, Haute-Marne, on 1 March 1814. The resulting Treaty of Chaumont was signed on 9 or 19 March 1814 although it was dated 1 March by Emperor Alexander I of Russia, Austrian Emperor Francis II (with Prince Metternich), King Frederick William III of Prussia, and British Foreign Secretary Lord Castlereagh. The treaty called for Napoleon to give up all conquests and thus to revert France to its pre-revolutionary borders in exchange for a ceasefire. If Napoleon rejected the treaty, the Allies pledged to continue the war. If Napoleon accepted, he would be allowed to continue to rule as the Emperor of the French and to keep a dynasty. The following day, Napoleon rejected the treaty, which ended his last chance of a negotiated settlement.

The emperor of Austria (German: Kaiser von Österreich, Latin: Imperator Austriae) was the ruler of the Austrian Empire and later the Austro-Hungarian Empire. The hereditary imperial title and office was proclaimed in 1804 by Francis II, Holy Roman Emperor, a member of the House of Habsburg-Lorraine, and continually held by him and his heirs until Charles I relinquished power in 1918.

The emperors retained the title of Archduke of Austria. The wives of the emperors held the title empress, while other members of the family held the titles of archduke or archduchess.

The Peace of Pressburg was signed in Pressburg (today Bratislava) on 26 December 1805 between French Emperor Napoleon Bonaparte and Holy Roman Emperor Francis II, as a consequence of the French victory over the Russians and Austrians at the Battle of Austerlitz (2 December). A truce was agreed on 4 December, and negotiations for the treaty began. The treaty was signed by Johann I Joseph, Prince of Liechtenstein, and the Hungarian Count Ignác Gyulay for the Austrian Empire and Charles Maurice de Talleyrand for France.

Beyond the clauses establishing "peace and amity" and the Austrian withdrawal from the Third Coalition, the treaty also mandated substantial territorial concessions by the Austrian Empire. The French gains of the previous treaties of Campo Formio and Lunéville were reiterated, while recent Austrian acquisitions in Italy and southern Germany were ceded to France and Bavaria, respectively. The scattered Austrian holdings in Swabia were passed to French allies – the King of Württemberg, and the Elector of Baden – while Bavaria received Tyrol and Vorarlberg. Austrian claims on those German states were renounced without exception. Venetia, Istria, and Dalmatia were incorporated into the Kingdom of Italy, of which Napoleon had become king earlier that year. The Principality of Lucca and Piombino was recognized as independent from the Holy Empire. Augsburg, previously an independent Free Imperial City, was ceded to Bavaria. As a minor compensation, the Austrian Empire annexed the Electorate of Salzburg, which had been under Habsburg rule since 1803. The elector, the Austrian Emperor's brother, was compensated with the Duchy of Würzburg, created from territories of the former prince-bishopric.

The Electorate of Baden (German: Kurfürstentum Baden) was a State of the Holy Roman Empire from 1803 to 1806. In 1803, the Imperial diet bestowed the office of Prince-elector to Charles Frederick, but in 1806, Francis II dissolved the Empire. Baden then achieved sovereignty, and Charles Frederick became Grand Duke.