Third Italian War of Independence

Victor Emmanuel II of Savoy had been proclamated King of Italy on 17 March 1861 but did not control Venetia or the much reduced Papal States. The situation of the Irredente (a later Italian term for part of the country under foreign domination, literally meaning un-redeemed) was an unceasing source of tension in the domestic politics of the newly created Kingdom, as well as being a cornerstone of its foreign policy.

The first attempt to seize Rome was orchestrated by Giuseppe Garibaldi in 1862. Confident in the King's neutrality, he set sail from Genoa to Palermo. Collecting 1,200 volunteers, he sailed from Catania and landed at Melito, in Calabria, on 24 August to reach Mount Aspromonte, with the intention to travel northwards up the peninsula to Rome. The Piedmontese General Enrico Cialdini, however, sent a division under Colonel Pallavicino to stop the volunteer army. Garibaldi himself was wounded in the ensuing battle, and taken prisoner along with his men.[4]

The increasing discord between Austria and Prussia over the German Question turned into open war in 1866, offering Italy an occasion to capture Venetia. On 8 April 1866, the Italian government signed a military alliance with Prussia,[5] through the mediation of Emperor Napoleon III of France. Italian armies, led by General Alfonso Ferrero La Marmora, were to engage the Austrians on the southern front. Simultaneously, taking advantage of their perceived naval superiority, the Italians planned to threaten the Dalmatian coast and seize Trieste.[6]

Allegory of Venice (lion) hoping to join Italy (woman).

Upon the outbreak of the war, the Italian military was hampered by the following factors:

• The problematic amalgamation of the armies of the Kingdom of Sardinia and the Kingdom of the Two Sicilies, the two largest components of the new Kingdom of Italy. There were disputes among the chain of command as former enemies were now serving alongside one another.[7] Added to this was the resentment and bitter resistance in Southern Italy that followed the annexation of the Kingdom of the Two Sicilies by Italy;
• The even stronger rivalry between the two navies which had formed the unified Italian Navy, the Regia Marina.

Prussia opened hostilities on 16 June 1866 by attacking several German states allied with Austria. Three days later, Italy declared war on Austria, starting military operations on 23 June.

The Italian forces were divided into two armies: the first, under La Marmora himself, was deployed in Lombardy, west of the Mincio River, aiming toward the powerful Quadrilatero fortress of the Austrians; the second, under Enrico Cialdini, in Romagna, south of the Po River, aiming toward Mantua and Rovigo.

La Marmora moved first through Mantua and Peschiera del Garda, but was defeated at the Battle of Custoza on 24 June and retreated in disorder back across the Mincio river. Cialdini, on the other hand, did not act offensively for the first part of the war, conducting only several shows of force and failed to besiege the Austrian fortress of Borgoforte, south of the Po.

Following the defeat at Custoza, the Italians reorganized in preparation for a presumed Austrian counter-offensive. The Austrians took this opportunity to raid Valtellina and Val Camonica (battle of Vezza d'Oglio).

Battle of Bezzecca

The naval battle of Lissa

The course of the war, however, was to turn in Italy's favor thanks to Prussian victories in Bohemia, especially the decisive Battle of Königgrätz (or Sadowa) on 3 July 1866. The Austrians were compelled to redeploy one of their three army corps from Italy to Vienna. The remaining Austrian forces in the theatre concentrated their defenses around Trentino and Isonzo.

On 5 July 1866, the Italian government received news of a mediation effort by Napoleon III for a settlement of the situation, which would allow Austria to receive favorable conditions from Prussia, and, in particular, to maintain Venice. The situation was embarrassing for Italy, as its forces had been beaten back in the only battle to date. As the Austrians were redeploying more and more troops to Vienna to defend it against the Prussians, La Marmora was urged to take advantage of his force's numerical superiority, score a victory, and thus improve the situation for Italy at the bargaining table.

On 14 July, during a council of war held in Ferrara, the new Italian war plans were decided, according to the following points:

• Cialdini was to lead the main army of 150,000 troops through the Venetia, while La Marmora, with roughly 70,000 men, would tie down Austrian forces in the Quadrilatero;
• the Italian Navy, commanded by Admiral Carlo di Persano was to set sail from Ancona with the objective of seizing Trieste.[6]
• Garibaldi's volunteers (named Cacciatori delle Alpi), reinforced by a division of regular infantry, were to advance into Trentino, with the eventual objective of capturing the province's capital, Trento.

Cialdini crossed the Po on 8 July, advancing to Udine on 22 July without encountering the Austrian army.[6] In the meantime, Garibaldi's volunteers had advanced from Brescia in the direction of Trento in the Invasion of Trentino, winning the battle of Bezzecca on 21 July. Cialdini's and Garibaldi's advances were overshadowed, however, by the unexpected defeat of the Italian Navy at the Battle of Lissa on 20 July.

On 26 July, a mixed Italian force of bersaglieri and cavalry defeated an Austrian force guarding the crossing of the Torre river and reached present-day Romans d'Isonzo in the Battle of Versia. This marked the maximum Italian advance into Friuli. However, with the cessation of Austro-Prussian hostilities, the Austrians looked ready to send reinforcements to Italy. Unwilling to risk another defeat and facing the risk of being severely outnumbered by Austrian reinforcements, the Italians were compelled to come to the peace table. On 9 August, Garibaldi was ordered in a telegraph by the Army High Command to evacuate Trentino. His reply was simply "Obbedisco" ("I shall obey") and became famous in Italy soon after. The cessation of hostilities was agreed to at the Armistice of Cormons signed on 12 August, followed by the Treaty of Vienna on 3 October 1866.

On July 1866, after the Prussian victory over Austria, the armistice of Nikolsburg ended the hostilities between the two countries. The Austrians withdrew to the Isonzo River, leaving Venice to Italian hands.[8] France and Prussia pressured Italy to conclude an armistice on its on with Austria.[8] The cessation of hostilities was agreed to at the Armistice of Cormons signed on 12 August, followed by the Treaty of Vienna on 3 October 1866.

The terms of the Peace of Prague included the giving of the Iron Crown of Lombardy to the Italian king and the cession of Venetia to France, as Napoleon III was acting as intermediary between Prussia and Austria. The Austrians also refused to surrender Venetia directly to Italy as the Italian army had not decisively defeated the Austrian army. The Italian government felt humiliated that it was not involved in the Austro-Prussian peace talks, and that Italy was to receive Venetia as a gift from France.[9] The Italian government thus demanded it would only annex Venetia after a plebiscite, in order for it to appear as the will of the people rather than a French gift.[9] The Peace of Prague was followed up by the Austrian-Italian Treaty of Vienna, which confirmed the cession of the territory to Italy.[10] The plebiscite was held on 21 and 22 October 1866, and the result was overwhelmingly in support of joining Italy. During this period, an uprising also occurred in Sicily, called The Seven and a Half Days Revolt.

The unification of Italy was completed by the Capture of Rome[11] and the annexation of Trentino, Friuli and Trieste at the end of First World War, also called in Italy the Fourth Italian War of Independence.

• First Italian War of Independence
• Second Italian War of Independence
• Austro-Prussian War
• Armistice of Cormons
• Garibaldi's Expedition against Rome
• Risorgimento
• Naval operations on Lake Garda, 1866

• Clodfelter, M. (2017). Warfare and Armed Conflicts: A Statistical Encyclopedia of Casualty and Other Figures, 1492-2015 (4th ed.). Jefferson, North Carolina: McFarland. ISBN 978-0786474707.CS1 maint: ref=harv (link)