Search for a casus belli

The Kingdom of Piedmont-Sardinia needed a presentable casus belli in order to attack the Kingdom of the Two Sicilies. This was needed for the House of Savoy, which however never gave any declaration of war against the Bourbon kingdom, a necessary condition since this was among the requirements presented to Cavour. The only occurrence that would have satisfied this requirement was an uprising from within. Such an event would have felt the alienation of the people from the dynasty that ruled in Naples and, particularly, the inability of Francis II of the Two Sicilies, to exercise government in his domains. Sicily, as shown by the history of the past decades, was fertile ground, and the liberal south, especially those returning after an amnesty granted by the young king, who worked in this direction for some time.^[10][11]

The Red Shirts

In March 1860, exile Rosolino Pilo exhorted Giuseppe Garibaldi to take charge of an expedition to liberate southern Italy from Bourbon rule.^[12] Garibaldi was against it at first, but eventually agreed.^[12] By May 1860, Garibaldi had collected 1,089 volunteers for his expedition to Sicily.^[13]

A total of 336 volunteers came from the contemporary Italian regions, including Genoa (156 volunteers),^[14] Tuscany (78 volunteers),^[15] Sicily (45 volunteers)^[16] and Naples (46 volunteers), with only 11 from Rome and the Papal States. ^[17] The largest number of volunteers came from Austrian Lombardy and Venetia, with 434 from Lombardy and 194 from Venetia.^[15][18] An additional 33 foreign volunteers joined the expedition.^[13] This included 14 ethnic Italians from the Trentino region of Austria, as well as István Türr and three other Hungarians.^[13] The volunteers came from middle-class backgrounds, with the vast majority being students and skilled craftsmen.^[12][15]

The 1,089 volunteers were unfavourably armed with obsolete muskets,^[13] and wore red shirts and grey trousers as their uniform.^[19] Thus they became known as the Redshirts.

During the night of 5 May, a small group led by Nino Bixio "seized" two steamships in Genoa from the Rubattino shipping company. (The ships were actually secretly provided by Rubattino.) The two ships were renamed Il Piemonte and Il Lombardo. At nearby Quarto dei Mille, the volunteers (including Francesco Crispi's wife, Rosalia Montmasson) embarked for Sicily.^[18]

According to Schneid, "Before embarking on the adventure, Garibaldi once again pledged his loyalty to Victor Emmanuel II and proclaimed that his intention was to conquer Sicily for the king. There is every indication that there was far more collusion between Cavour and Garibaldi, if not Victor Emmanuel and Garibaldi. After Garibaldi landed in Sicily, Admiral Persano received orders to support the expedition."^[20]

Landing in Sicily

Francesco Crispi

The ships were then accompanied by the British Royal Navy which consisted of HMS Hannibal followed by the gunboats HMS Argus and HMS Intrepid under the command of Admiral Rodney Mundy. They landed at Marsala, on the westernmost point of Sicily, on 11 May. With British ships present in the harbour, the Bourbon ships were deterred from interfering.^[21] The Lombardo was attacked and sunk only after the disembarkation had been completed, while the Piemonte was captured. The landing had been preceded by the arrival of Francesco Crispi and others, who had the task of gaining the support of the locals for the volunteers.

Calatafimi and Palermo

Giuseppe Garibaldi in Palermo

The Mille ('thousand') won a first battle at Calatafimi against around 2,000 Neapolitan troops on 15 May. The battle boosted the morale of the Mille and, at the same time, depressed the Neapolitans, who were poorly led by their often corrupt higher officers, and started to feel abandoned. Having promised land to every male who volunteered to fight against the Bourbons the ranks of the Mille enlarged to 1,200 with local men.^[22]

On 27 May, with the help of a popular insurrection organized by La Masa and Gilbrossa, Garibaldi took Porto Termini and began the Siege of Palermo. General Lanza had replaced Castelcicala, and had under his command 21,000 troops, and a squadron of warships. Yet, the British Admiral Mundy organized an armistice, and the garrison evacuated on 7 July, after King Francis II authorized the Neapolitan withdrawal.^{[20]: 62–63}

On 7 July, Garibaldi proclaimed himself Dictator of Sicily "in the name of Victor Emmanuel, King of Italy." He reorganized the Thousand into the Southern Army, with the arrival of Giacomo Medici's additional troops, weapons, and ammunition. Garibaldi then ordered Medici to advance towards Messina, Enrico Cosenz to advance upon Catania, and Nino Bixio to advance upon Syracuse, gathering more Sicilian volunteer irregulars. Francis II strengthened his Neapolitan garrisons at Messina and Syracuse.^[20]: 63

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  Battle of Calatafimi
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  The thousand cross the "Admiral's Bridge" in Palermo.
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  Garibaldi marches through conquered Palermo.

Neapolitan retreat and Battle of Milazzo

Francis II and Maria Sophie

Lithograph of Garibaldi and his Red Shirts at the Battle of Milazzo

The Bourbon troops were ordered to retreat eastwards and evacuate the island. An insurrection that had broken out in Catania on 31 May, led by Nicola Fabrizi, was crushed by the local garrison, but the order to leave for Messina meant that this Neapolitan tactical success would have no practical results.

At the time only Syracuse, Augusta, Milazzo and Messina remained in royal hands in Sicily. In the meantime, Garibaldi issued his first law. A levy failed to muster more than 20,000 troops, while the peasants, who hoped for immediate relief from the grievous conditions to which they were forced by the landowners, revolted in several localities. At Bronte, on 4 August 1860, Garibaldi's friend Nino Bixio bloodily repressed one of these revolts with two battalions of Redshirts.

The pace of Garibaldi's victories had worried Cavour, who in early July sent him a proposal of immediate annexation of Sicily to Piedmont. Garibaldi, however, refused vehemently to allow such a move until the end of the war. Cavour's envoy, La Farina, was arrested and expelled from the island. He was replaced by the more malleable Agostino Depretis, who gained Garibaldi's trust and was appointed as pro-dictator.

On 25 June 1860, King Francis II of the Two Sicilies issued a constitution. However, this late attempt to conciliate his moderate subjects failed to rouse them to defend the regime, while liberals and revolutionaries were eager to welcome Garibaldi.

On 20 July Garibaldi attacked Milazzo with 4,000 men, under the command of Medici and Cosenz, against Bosco's 4,500. On 1 August, Bosco surrendered with honours, and was taken by ship to Real Cittadella, which was soon under siege. Over the next three weeks, with firm control of Sicily, Garibaldi prepared to cross the Straits of Messina.^{[20]: 63–64}

Landing and conquest in Calabria

Giuseppe Missori landing in Calabria

On 19 August Garibaldi's men disembarked in Calabria, a move opposed by Cavour, who had written the Dictator a letter urging him to not cross the Straits of Messina. Garibaldi, however, disobeyed, an act which had the silent approval of King Victor Emmanuel.

According to Schneid, "The timing of Garibaldi's crossing of the Straits of Messina and the invasion of the Papal States was more than coincidence.^[20]: 65

The Bourbons had some 20,000 men in Calabria, but, apart from some episodes like that of Reggio Calabria, which was conquered at high cost by Bixio on 21 August, they offered insignificant resistance, as numerous units of the Bourbon army disbanded spontaneously or even joined Garibaldi's ranks. On 30 August a conspicuous Sicilian army, led by General Ghio, was officially disbanded at Soveria Mannelli, while only minor and dispersed units continued the fight. The Neapolitan fleet behaved in a similar way.

The end

Battle of Volturnus, 1 October 1860

Meeting between King Victor Emmanuel II and Garibaldi at Teano, 26 October 1860

On 6 September, King Francis II fled Naples for the fortress city of Gaeta, and moved his army to the Volturno river. Garibaldi took possession of Naples, and on 11 September, crossed the Papal frontier.^[20]: 65

On 11 September, Cavour instigated the invasion of the Papal States, led by Manfredo Fanti. The Papal Army was led by Louis Juchault de Lamoricière, though Pope Pius IX's hope that Napoleon III and Franz Josef I of Austria would come to his aid was unfounded. General Enrico Cialdini's IV Corps attacked Pesaro, Enrico Morozzo Della Rocca's V Corps advanced on Perugia, while Persano blockaded Ancona. On 18 September, the Papal Army under Lamoriciére were defeated during the Battle of Castelfidardo, and the siege of Ancona began, finally surrendering on 29 September. According to Schneid, "The fall of Ancona ended the campaign in the Papal States. The Piedmontese Army occupied most of Umbria and Marche."^{[20]: 65–67}

According to Schneid, "Garibaldi narrowly won the Battle of Volturno. The Southern Army placed Capua under siege, and the Piedmontese forces marched on Gaeta where the erstwhile Neapolitan king had taken refuge." The Savoia Brigade landed north of Capua, while Della Rocca's V Corps, and the rest of the Piedmontese Army, crossed the Neapolitan frontier.^[20]

A few days later (21 October) a plebiscite confirmed the annexation of the Kingdom of the Two Sicilies to the Kingdom of Sardinia by an overwhelming majority.

The end of the expedition is traditionally set with the famous meeting in Teano^[23] (northern Campania) between Victor Emmanuel and Garibaldi (26 October 1860). Others assign instead the end of the campaign to the King's entrance into Naples on 7 November.

However, the military campaign was not yet fully completed, as Francis II held out in Gaeta until February of the next year, when he finally surrendered to the Sardinian army led by Enrico Cialdini, and left for exile in the Papal States. Shortly thereafter, in March 1861, the new Kingdom of Italy (Regno d'Italia) was formally established.

Garibaldi asked the King to remain in the former Two Sicilies for a year as dictator. He also asked that his officers be integrated into the new Italian Army. When Victor Emmanuel refused to grant the dictator his request but agreed to integrate the men and officers, he returned to Caprera.

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  Garibaldi captures Reggio Calabria, 21 August 1860.
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  Garibaldi marching into Naples on horseback, 7 September 1860
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  Redshirt volunteers after the battle of Volturno
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  Giuseppe Barboglio, a Red Shirt volunteer of the Thousand, wearing the Marsala Medal