Kingdom of Sardinia and Aosta, dynastic possessions since the 11th century, the Principality of Piedmont (a possession built up in the 13th century), and the County of Nice (a possession since 1388). While in theory the traditional capital of the island of Sardinia and seat of its viceroys was Cagliari, the Piedmontese city of Turin was the "de facto" capital of Savoy. When the mainland domains of the House of Savoy were occupied and eventually annexed by Napoleonic France, the king of Sardinia made his permanent residence on the island for the first time in its history. The Congress of Vienna (1814–15), which
Kingdom of Sardinia Sardinia, including the city of Alghero and the semiautonomous Republic of Sassari, and added them to its direct domains. The Giudicato of Arborea, the only Sardinian state that remained independent of foreign domination, proved far more difficult to subdue. Threatened by the Aragonese claims of suzerainty and consolidation of the rest of the island, in 1353 Arborea, under the leadership of Marianus IV, started the conquest of the remaining Sardinian territories, which formed the Kingdom of Sardinia. In 1368 an Arborean offensive succeeded in nearly driving the Aragonese from the island, reducing the "Kingdom of Sardinia and Corsica" to just