The treaty of Vienna, signed on October 3, 1866 and approved on October 12, was a turning point in the alliance of Italy and the balance of power in Europe. Ending the hostilities of the Third War of Italian Independence, the treaty was a pivotal consequence for the Kingdom of Italy and marked the disappearing influence of the Austrian Empire. Alongside the Austro-Prussian War, the treaty reformed political edge, moving Venetia and parts of Friuli from Austrian to Italian control.
The treaty followed the Armistice of Cormons, signed on August 12, 1866, which stopped the clash between Italy and Austria. Under the treaty’s term, Austria ceded Venetia to the French Empire, which moved the region to Italy after a referendum confirmed the will of the local people. This agreement effectively concluded the dismantling of the Habsburg-ruled Kingdom of Lombardy-Venetia, with Lombardy having been ceded to the Kingdom of Sardinia in 1859 under the Treaty of Zurich.
The treaty’s success was part of a broader Italian nationalist movement that had achieved momentum since the revolution of 1848. The Kingdom of Piedmont-Sardinia, led by Prime Minister Camillo Benso, Count of Cavour, had consistently worked toward the alliance of Italy. The previous unification with France during the Second Was of Italian Independence had secured Lombardy for the Italian cause and Italy allied with Prussia during its clash with Austria in 1866, despite suffering military defeat at Custoza and Lissa, the Italian power, supported by Giusseppe Garibaldi’s volunteers, made momentous gain in Trentino. However, it was Austria’s defeat by Prussia at the Battle of Sadowa that forced the Austrian Empire into concession.
The treaty was contributory in the rise of the Kingdom of Italy as sovereign state and a growing power in Europe. It forced Austria to recognise Italian sovereignty over Venetia, weakening the Austrian Empire’s power in Italy and signaling its decline as a dominant force in Europe. The treaty was a significant step in the process of Italian alliance, which would be concluded in 1870 with the capture of Rome. Furthermore, it redefined Europe’s political landscape, marking Italy’s emergence as an important power while underlining the disappearing influence of the Habsburg monarchy.
