The Austrian predominance in Northern Italy 1815–66
On 17 October 1797 at the Peace of Campo Formio the Austrian Netherlands, the Rhineland and Lombardy are added to the territories directly under French administration. As compensation, Austria gains Venice and parts of the territories of the Venetian Republic. By occupying Venice, the Austrian Empire inherits Venice’s trade relations with the eastern Mediterranean.

From 18 September 1814 to 4 March 1815, the European powers discuss the territorial settlement of Europe at the Great Peace Congress of Vienna. Austria regains Lombardy and takes the territories of the Venetian Republic as compensation for the loss of the Austrian Netherlands.
The Congress of Berlin and Austrian predominance in the Western Balkans
At the Congress of Berlin in June 1878 a considerably territorially reduced Bulgaria is confined to its northern territories principally tributary to Turkey. The great powers: Germany, Russia, France, Great Britain, Austria and Turkey grant Austria the right to occupy and administer Bosnia and Herzegovina and concede the military occupation of the Sanjak of Novibazar.

The Austrian army occupying Bosnia Herzegovina goes into battle against the Bosnian insurgents, which turns out to be a costly military campaign. In 1881 the last parts of the Croatian Military Frontier is merged with Hungary, with substantial Serb communities in all of these territories. The Austrian Government subordinates most of the Serb national rights to the Magyar-Croatian Administration. This, and the occupation of Bosnia Herzegovina, puts a strain on relations with both Turkey and Serbia.
The road to World War I
In June 1903, the young pro-Austrian King of Serbia Alexander Obrenović is brutally murdered in an officers’ conspiracy. With replacement of the pro-Austrian Serbian Dynasty by the pro-Russian Dynasty under Peter I the balance of power between Austria and Russia in the Balkans changes. In July 1908, the “Young Turk” nationalist revolution transforms the Ottoman Empire into a constitutional monarchy. The revolution rapidly disintegrates the European territories of the Ottoman Empire. The Austrian annexation of Bosnia-Herzegovina on 6 October 1908 causes a major crisis in Europe, adding to hostilities between Austria-Hungary and Serbia. To the Austrian-Serbian rivalry was added the Austro-Russian rivalry for influence in the Balkan Peninsula. On 28 June 1914 the successor to the throne, Archduke Francis Ferdinand of Austria was shot in Sarajevo by a Bosnian youth of Serb origin. His assassination triggers the outbreak of World War I. Austria declares war on Serbia on 28 July 1914.