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.
Italy
In the south, Sicily had become an Islamic emirate in the 9th century, thriving until the Italo-Normans conquered it in the late 11th century together with most of the Lombard and Byzantine principalities of southern Italy. Through a complex series of events, southern Italy developed as a unified kingdom, first under the House of Hohenstaufen, then under the Capetian House of Anjou and, from the 15th century, the House of Aragon. In Sardinia, the former Byzantine provinces became independent states known in Italian as Giudicati, although some parts of the island became controlled by Genoa or Pisa until the Aragonese annexation in the 15th century. The Black Death pandemic of 1348 left its mark on Italy by killing perhaps one third of the population. However, the recovery from the plague led to a resurgence of cities, trade and economy which allowed the bloom of Humanism and Renaissance, that later spread to Europe.