of the Austrian Succession (1740–1748) and the Seven Years' War (1756–1763). Subsequently, Austria lost Silesia to Prussia. Austria also lost prior conquests from the Ottomans except Banat of Temeswar and Syrmia in the Austro-Russian–Turkish War despite being allied with Russia. These Silesian Wars initiated a long-standing tension between Austria and Prussia. Maria Theresa effectively reigned as Empress through her husband, Francis Stephen of Lorraine (d. 1765) and they founded the new dynasty of Habsburg-Lorraine. During her reign, extensive reforms were initiated, and when Francis died in 1765, these were continued by her son, Joseph II (Emperor 1765–1790; Archduke 1780–1790). However, his successor, his brother, Leopold II (1790–1792), was much more conservative. The next emperor, his son Francis II (1792–1835), found himself at war with France in the First (1792–1797) and Second (1798–1802) Coalition wars, the prelude to the Napoleonic Wars (1803–1815), in which Austria lost further territory. Following further Austrian losses in the Third Coalition War (1803–1806) the future of the Habsburg Empire looked increasingly uncertain. Napoleon had declared himself Emperor of France in May 1804 and was busy reorganising much of the lands of the Holy Roman Empire, and looked to be assuming the title of emperor too, as a second Charlemagne. Francis II responded by proclaiming the Empire of Austria in August, taking the new title of Emperor. In 1806, having held both titles in the interim, he resigned the imperial crown of the Holy Roman Empire of the German Nation, which then ceased to exist. Following the Congress of Vienna, Austria became part of the German Confederation till the Austro-Prussian War of 1866. In the 19th century nationalist movements within the empire became increasingly evident, and the German element became increasingly weakened, whilst most of Austria's Italian-speaking lands were gained by the new Kingdom of Italy. With Austria's expulsion from the German Confederation following its defeat by Prussia in the war in 1866 the Dual Monarchy with Hungary was created by the Austro-Hungarian Compromise in 1867. This succeeded in reducing but not removing nationalist tensions as it left mostly Slavic peoples and Romanians dissatisfied; dissatisfactions which were to boil over with the 1914 assassination of the heir to the throne of Austria-Hungary, Archduke Franz Ferdinand in Sarajevo, and the ensuing chain reaction resulting in the First World War. The losses of the war resulted in the collapse of the empire and dynasty in 1918. The non-German ethnic