Sardinia world (22 centenarians/100,000 inhabitants). Sardinia is the first discovered Blue Zone, a demographic and/or geographic area in the world with an oversize concentration of centenarians and supercentenarians. In 2016 there were 50,346 foreign national residents, forming 3% of the total Sardinian population. The most represented nationalities were: Sardinia's most populated cities are Cagliari and Sassari. The Metropolitan City of Cagliari has 431,302 inhabitants, or about ¼ of the population of the entire island. Eurostat has identified in Sardinia two Functional Urban Areas: Cagliari, with 477,000 inhabitants, and Sassari, with 222,000 inhabitants. Sardinia is one of the five Italian autonomous regions,
Kingdom of Sardinia restructured Europe after Napoleon's defeat, returned to Savoy its mainland possessions and augmented them with Liguria, taken from the Republic of Genoa. In 1847–48, in a "perfect fusion", the various Savoyard states were unified under one legal system, with the capital in Turin, and granted a constitution, the "Statuto Albertino". There followed the annexation of Lombardy (1859), the central Italian states and the Two Sicilies (1860), Venetia (1866), and the Papal States (1870). On 17 March 1861, to more accurately reflect its new geographic extent, the Kingdom of Sardinia changed its name to the Kingdom of Italy, and its capital