Cappai des Baux, originally Çapay viscounts of Bas (Baux), is the name of an old Aragonese noble family who came to Sardinia in the 14th century with the king James II of Aragon during his campaign to conquer the island. The Cappai played a major role in the history of Sardinia, where they received many fiefs by the king who wanted reward them for the help that they've given him to conquer the island. During the Middle Ages they got the titles of Count of Villasalto, Marquis of Muravera and Villarios, and the most important of Prince of Bas, which they inherited because they've been related with the kings of Arborea of the Bas-Serra family.