Cavour, diplomacy, and the making of the Kingdom of Italy (1859-1861)

Cavour's path to war ran through secret diplomacy. Meeting Napoleon III at Plombières-les-Bains on 20-21 July 1858, Cavour secured a French promise of military assistance against Austria in exchange for the cession of Savoy and Nice to France, provided Austria could be made to appear the aggressor. Austria obliged by delivering an ultimatum on 23 April 1859, which Cavour deliberately rejected, and Austria declared war three days later, opening the Second Italian War of Independence. French and Piedmontese forces won decisive victories at Magenta (4 June 1859) and, in the bloodiest battle fought in Europe since Leipzig, at Solferino and San Martino (24 June 1859) — a battle whose carnage so shocked the Genevan witness Henry Dunant that his account inspired the founding of the Red Cross. Alarmed by the casualties and by the risk of Prussian intervention, Napoleon III negotiated a separate armistice with Austria at Villafranca (11 July 1859) without consulting Cavour, who resigned in protest; the resulting Treaty of Zurich ceded Lombardy to Piedmont but left Venetia under Austrian rule.