Kingdom of Sardinia
On 17 March 1861, law no. 4671 of the Sardinian Parliament proclaimed the Kingdom of Italy, so ratifying the annexations of all other Apennine states, plus Sicily, to the Kingdom of Sardinia. The institutions and laws of the Kingdom were quickly extended to all of Italy, abolishing the administrations of the other regions. Piedmont became the most dominant and wealthiest region in Italy and the capital of Piedmont, Turin, remained the Italian capital until 1865, when the capital was moved to Florence. But many revolts exploded throughout the peninsula, especially in southern Italy, and on the island of Sicily, because of the perceived unfair treatment of the south by the Piedmontese ruling class. The House of Savoy ruled Italy until 1946 when Italy was declared a republic by referendum. In this referendum the southern regions, including Sardinia, voted overwhelmingly in favor of the House of Savoy, with the results being 63.8% in favor of maintaining the monarchy.
Italian unification
The 2nd War of Italian Independence began in April 1859 when the Sardinian Prime Minister Count Cavour found an ally in Napoleon III. Napoleon III signed a secret alliance and Cavour provoked Austria with military maneuvers and eventually created the war in April 1859. Cavour called for volunteers to enlist in the Italian liberation. The Austrians planned to use their army to beat the Sardinians before the French could come to their aid. Austria had an army of 140,000 men, while the Sardinians had a mere 70,000 men by comparison. However the Austrians' numerical strength was outweighed by an ineffectual leadership appointed by the Emperor on the basis of noble lineage, rather than military competency. Their army was slow to enter the capital of Sardinia, taking almost ten days to travel the . By this time, the French had reinforced the Sardinians, so the Austrians retreated. 
Napoleon III's plans worked and at the Battle of Solferino, France defeated Austria and forced negotiations. The settlement, by which Lombardy was annexed to Sardinia, left Austria in control of Venice. 
Sardinia eventually won the Second War of Italian Unification due to statesmanship instead of 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.