Italian unification, also known as the Risorgimento, was the political and social movement that consolidated different states of the Italian peninsula into the single state of the Kingdom of Italy in the 19th century.
The process began with the revolutions of 1848, inspired by previous rebellions in the 1820s and 1830s that contested the outcome of the Congress of Vienna, and was completed when Rome became the capital of the Kingdom of Italy.
The term, which also designates the cultural, political and social movement that promoted unification, recalls the romantic, nationalist and patriotic ideals of an Italian renaissance through the conquest of a unified political identity that, by sinking its ancient roots during the Roman period, “suffered an abrupt halt [or loss] of its political unity in 476 AD after the collapse of the Western Roman Empire“. Some of the terre irredente did not join the Kingdom of Italy until 1918 after Italy defeated Austria–Hungary in World War I. For this reason, sometimes the period is extended to include the late 19th century and the First World War (1915–1918), until the 4 November 1918 Armistice of Villa Giusti, which is considered the completion of unification. This view is followed, for example, at the Central Museum of Risorgimento at the Vittoriano.
Many leading Carbonari revolutionaries wanted a republic, two of the most prominent being Giuseppe Mazzini and Giuseppe Garibaldi. Garibaldi, a native of Nice (then part of Piedmont), participated in an uprising in Piedmont in 1834 and was sentenced to death. He escaped to South America, though, spending fourteen years in exile, taking part in several wars, and learning the art of guerrilla warfare before his return to Italy in 1848.
Sardinia eventually won the Second War of Italian Unification in 1859 through statesmanship rather than armies or popular election. The final arrangement was ironed out by “back-room” deals instead of in the battlefield. This was because neither France, Austria, nor Sardinia wanted to risk another battle and could not handle further fighting. All of the sides were eventually unhappy with the final outcome of the 2nd War of Italian Unification and expected another conflict in the future.
Francis II of the Two Sicilies, the son and successor of Ferdinand II (the infamous “King Bomba“), had a well-organized army of 150,000 men. But his father’s tyranny had inspired many secret societies, and the kingdom’s Swiss mercenaries were unexpectedly recalled home under the terms of a new Swiss law that forbade Swiss citizens to serve as mercenaries. This left Francis with only his mostly unreliable native troops. It was a critical opportunity for the unification movement. In April 1860, separate insurrections began in Messina and Palermo in Sicily, both of which had demonstrated a history of opposing Neapolitan rule. These rebellions were easily suppressed by loyal troops.
On 14 May Garibaldi proclaimed himself dictator of Sicily, in the name of Victor Emmanuel. After waging various successful but hard-fought battles, Garibaldi advanced upon the Sicilian capital of Palermo. With Palermo deemed insurgent, Neapolitan general Ferdinando Lanza, arriving in Sicily with some 25,000 troops, furiously bombarded Palermo nearly to ruins. With the intervention of a British admiral, an armistice was declared, leading to the Neapolitan troops’ departure and surrender of the town to Garibaldi and his much smaller army.
This resounding success demonstrated the weakness of the Neapolitan government. Garibaldi’s fame spread and many Italians began to consider him a national hero. Having conquered Sicily, Garibaldi proceeded to the mainland, crossing the Strait of Messina with the Neapolitan fleet at hand. The garrison at Reggio Calabria promptly surrendered. As he marched northward, the populace everywhere hailed him, and military resistance faded: on 18 and 21 August, the people of Basilicata and Apulia, two regions of the Kingdom of Naples, independently declared their annexation to the Kingdom of Italy.
Meanwhile, Naples had declared a state of siege, and on 6 September the king gathered the 4,000 troops still faithful to him and retreated over the Volturno river. The next day, Garibaldi, with a few followers, entered by train into Naples, where the people openly welcomed him.
The progress of the Sardinian army compelled Francis II to give up his line along the river, and he eventually took refuge with his best troops in the fortress of Gaeta. European allies refused to provide him with aid, and food and munitions became scarce, and disease set in, so the garrison was forced to surrender. Nonetheless, ragtag groups of Neapolitans loyal to Francis fought on against the Italian government for years to come.
The fall of Gaeta brought the unification movement to the brink of fruition—only Rome and Venetia remained to be added. On 18 February 1861, Victor Emmanuel assembled the deputies of the first Italian Parliament in Turin. On 17 March 1861, the Parliament proclaimed Victor Emmanuel King of Italy, and on 27 March 1861 Rome was declared Capital of Italy, even though it was not yet in the new Kingdom.