History of Sardinia
In the Early Middle Ages, through barbarian movements, the waning of the Byzantine Empire influence in the western Mediterranean and the Saracen raids, the island fell out of the sphere of influence of any higher government. This led to the birth of four kingdoms called "Judicates" (Latin: "Judicati"; Sardinian: "Judicados") in the 8th through 10th centuries. Falling under papal influence, Sardinia became the focus of the rivalry of Genoa and Pisa, the Judicates and the Crown of Aragon, which eventually subsumed the island as the Kingdom of Sardinia in 1324. The Kingdom was to last until 1718, when it was ceded to the Piedmontese House of Savoy; later, in 1861, it would thus become the Kingdom of Italy and finally in 1946 the Italian Republic.
Kingdom of Sardinia
When it was acquired by the Duke of Savoy in 1720, it was a former Iberian state with weak institutions. However, the Savoyards united it with their possessions on the Italian mainland and, by the time of the Crimean War in 1853, had built the resulting kingdom into a strong power. The composite state under the rule of Savoy in this period may be called Savoy-Sardinia or Piedmont-Sardinia, or even the Kingdom of Piedmont to emphasise that the island of Sardinia was of secondary importance to the monarchy. The formal name of the entire Savoyard state was the "States of His Majesty the King of Sardinia". Its final capital was Turin, the capital of Savoy since the Middle Ages.