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.
History of Sardinia
In 1323 an Aragonese army, under Alfonso, son of King James II, disembarked near Palma di Sulcis, in Southern Sardinia. After the fall of Villa di Chiesa the Pisans were defeated again, both by land and sea, at Lucocisterna and in the gulf of Cagliari, and were forced to leave the island, maintaining only Castel di Castro until 1326. The Cagliari area as well as Gallura thus became part of the first nucleus of the Kingdom of Sardinia, established nominally by Pope Boniface VIII in 1297, that was included in the Crown of Aragon.