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.
Republic of Genoa
The republic began when Genoa became a self-governing commune within the imperial Kingdom of Italy, and ended when it was conquered by the French First Republic under Napoleon and replaced with the Ligurian Republic. Corsica was ceded to France in the Treaty of Versailles of 1768. The Ligurian Republic was annexed by the First French Empire in 1805; its restoration was briefly proclaimed in 1814 following the defeat of Napoleon, but it was ultimately annexed by the Kingdom of Sardinia in 1815.