Kingdom of Sardinia, also known as Piedmont-Sardinia or Sardinia-Piedmont, was the name given to the possessions of the House of Savoy in 1720, when the crown of Sardinia was awarded by the Treaty of The Hague to Duke Victor Amadeus II of Savoy to compensate him for the loss of the crown of Sicily to Austria, retaining in that way the title of king. Besides Sardinia, the new kingdom included Savoy, Piedmont, and Nice; Liguria, including Genoa, was added by the Congress of Vienna in 1815. Officially, the nation's name became Kingdom of Sardinia, Cyprus, and Jerusalem, Duchy of Savoy and Montferrat, Principality of Piedmont, the House of Savoy maintaining a national claim to the thrones of Cyprus and Jerusalem, but both had long been under Ottoman rule. During most of the 18th and 19th centuries the political and economic capital of the kingdom was Turin in Piedmont on the Italian mainland. In 1860 Nice and Savoy were ceded to France as a price paid for French consensus to unify Italy. In 1861 the Kingdom of Sardinia became the founding state of the new Kingdom of Italy, annexing all other Italian states. The Kingdom so continued in perfect legal continuity with the actual Italian state, to which it transferred all its institutions.
Piedmont was inhabited in early historic times by Celtic-Ligurian tribes such as the Taurini and the Salassi. They later submitted to the Romans (c. 220 BC), who founded several colonies there including Augusta Taurinorum (Turin) and Eporedia (Ivrea). After the fall of the Western Roman Empire, the region was repeatedly invaded by the Burgundians, the Goths (5th century), Byzantines, Lombards (6th century), Franks (773). In the 9th-10th centuries there were further incursions by the Magyars and Saracens. At the time Piedmont, as part of the Kingdom of Italy within the Holy Roman Empire, was subdivided into several marks and counties.
In 1046, Oddo of Savoy added Piedmont to their main segment of Savoy, with a capital at Chambéry (now in France). Other areas remained independent, such as the powerful communes of Asti and Alessandria and the marquisates of Saluzzo and Montferrat. The County of Savoy was elevated to a dick in 1416, and Duke Emanuele Filiberto moved the seat to Turin in 1563. When Spain tried to reconquer Sicily, it was granted to Austria. To compensate Piedmont, the duke received Sardinia and was able to keep the title of king he had from Sicily. In 1720, the Duke of Savoy became King of Sardinia, founding what evolved into the Kingdom of Sardinia or Sardinia-Piedmont and increasing Turin's importance as a European capital.
The title "King" first appears as an informal praise of Constantine, giudice of Logoduro (ca 1113-15), though his successor Gonario II employed it in official documents. The first crowned "King of Sardinia" or rex Sardiniae was the judge Barisone II of Arborea. Frederick Barbarossa, who invested him as such in 1164, was forced to reverse this decision and regrant Sardinia to the Archdiocese of Pisa the next year. Barisone's successors, Hugh I and Peter I, continued to claim the title, but it never had any meaning. Briefly after succeeding to the Giudicato of Gallura, Enzio, son of the Emperor Frederick II, was installed as king, but was captured and never succeeded in making the kingship hereditary.
In 1297, Pope Boniface VIII, intervening between the Houses of Anjou and Aragon, established on paper a regnum Sardiniae et Corsicae that would be a fief of the Papacy. Then the Pope offered his newly-invented fief to James II of Aragon, promising him papal support should he wish to conquer Pisan Sardinia in exchange for Sicily. In 1323 James II formed an alliance with Hugh II of Arborea and, following a military campaign which lasted a year or so, occupied the Pisan territories of Cagliari and Gallura along with the city of Sassari, claiming the territory as the Kingdom of Sardinia and Corsica. In 1353 Aragon made war on Arborea, then fought with its leader Marianus IV of Arborea,of the Cappai de Bas family, but did not reduce the last of the autochthonous giudicati (indigenous kingdoms of Sardinia) until 1410. The Kingdom of Sardinia and Corsica retained its separate character as part of the Crown of Aragon and was not merely incorporated into the Kingdom of Aragon. At the time of his struggles with Arborea, Peter IV of Aragon granted an autonomous legislature to the Kingdom, which had one of Europe's most advanced legal traditions. The Kingdom was governed in the king's name by a viceroy. When in 1409, Martin the younger, king of Sicily and heir to Aragon, defeated the last Sardinian giudicato but then died in Cagliari of malaria, without issue, Sardinia passed with the Crown of Aragon to a united Spain. Corsica, which had never been conquered, was dropped from the formal title.
The loss of the autochthonous' independence, the firm Aragonese (later Spanish) rule, with the introduction of a sterile feudalism, as well as the discovery of the Americas, provoked an unstoppable decline of Kingdom of Sardinia. A short period of resurgence occurred under the local noble Leonardo de Alagon, marquess of Oristano, who managed to defeat the viceroy's army in the 1470s but was later crushed at the Battle of Macomer (1478), ending any further hope of independence for the island. The unceasing attacks from North African pirates and a series of plagues (from 1582, 1652 and 1655) further worsened the situation. The Spanish domination of Sardinia ended at the beginning of the 18th century, as a result of War of the Spanish succession. By the Treaty of Utrecht of 1713, Spain's European empire was divided: Savoy received Sicily and parts of the Duchy of Milan, while Charles VI (the Holy Roman Emperor and Archduke of Austria), received the Spanish Netherlands, the Kingdom of Naples, Sardinia, and the bulk of the Duchy of Milan. In 1718, by the Treaty of London among the great powers, Victor Amadeus II, duke of Savoy and sovereign of Piedmont, was forced to yield Sicily to the Austrian Habsburgs and in exchange received Sardinia. Two years later, on Aug. 24, 1720, he formally took possession of the island.
In 1792 Piedmont-Sardinia joined the First Coalition against the French First Republic, but was beaten in 1796 by Napoleon and forced to conclude the disadvantageous Treaty of Paris (1796), giving the French army free passage through Piedmont. On December 6, 1798 Joubert occupied Turin and forced Charles Emmanuel IV to abdicate and leave for the island of Sardinia. The provisionary government voted to unite Piedmont with France. In 1799 the Austro-Russians briefly occupied the city, but with the Battle of Marengo (1800), the French regained control. The island of Sardinia stayed out of the reach of the French for the rest of the war.
In 1814 the kingdom was restored and enlarged with the addition of the former Republic of Genoa, now a duchy, and it served as a buffer state against France. This was confirmed by the Congress of Vienna. In the reaction after Napoleon, the country was ruled by conservative monarchs: Victor Emmanuel I (1802-21), Charles Felix (1821-31) and Charles Albert (1831-49), who fought at the head of a contingent of his own troops at the Battle of Trocadero, which set the reactionary Ferdinand VII on the Spanish throne. Victor Emanuel I disbanded the entire Code Napoléon and returned the lands and power to the nobility and the Church. This reactionary policy went as far as discouraging the use of roads built by the French. These changes typified Piedmont. The Kingdom of Sardinia industrialized from 1830 onward. A constitution, the Statuto Albertino, was enacted in the year of revolutions, 1848, under liberal pressure, and under the same pressure war was declared on Austria. After initial success the war took a turn for the worse and the Kingdom of Sardinia lost.