While
Peter II, son of Hugh, has been accused by historians of impoverishing his realm of glory, his son
Marianus II expanded it substantially, even briefly ruling over a majority of the island. During the final decades of the 13th century, three other
giudicati fell into the hands of either Pisa or Genoa or one of their great families, but Arborea remained independent.
Hugh II (ruled 1321 – 1336), great-grandson of Marianus II, headed up a faction which favoured
James II of Aragon, who had been promised the island by the pope, as overlord. He supported the
Infante Alfonso in his campaign (1323 – 1324) to
conquer the island from Pisa. In 1336, Hugh II was succeeded by his son
Peter III (died 1345). His brother
Marianus IV (ruled 1353 – 1375) was the only Sardinian ruler to be known as "the Great". He was educated at the
Crown of Aragon's royal court, but later turned against his cultural allies and led a victorious revolt against the
aragonese invaders
Sardinian–Catalan war. With Marianus IV the great, a period of splendour commenced in the Kingdom of Arborea. Oral traditions were codified and new legislation enacted. Army and tactics were reformed. With the exception of Cagliari,
Alghero, and
Sassari (then under
Brancaleone Doria), Marianus conquered the whole of the island, making Arborea the strongest any of the island's judicates had ever been. Marianus was succeeded by his son
Hugh III, who furthered his father's legislation and died without descendants in 1383. A republic was proclaimed, but the crown was claimed by
Eleanor De Serra Bas, elder sister of Hugh III, who was married to Brancaleone Doria. She succeeded to power in 1387. Eleanor was technically regent on behalf of her sons
Frederick and, subsequently,
Marianus V. She died in 1404 and Marianus in 1407; after the latter's death the succession passed to
William III of Narbonne, grandson of Beatrice, Eleanor's sister. He defended the island against the troops of King
Martin of Aragon, but
Martin I of Sicily (son of Martin of Aragon) vanquished them in the
Battle of Sanluri on 30 June 1409. Martin's sudden death made possible a recovery and occupation of Sassari and part of Logudoro as well as reclamation of the title of Judge of Arborea by William. However, all the Arborean castles fell after a renewed Aragonese offensive; Oristano fell in March 1410 without resistance.
Leonard Cubell laid claim to the title of Judge of Arborea, but was compelled in Oristano by
Pedro de Torrelles to renounce his claim, after which he was given the
Marquisate of Oristano and County of
Goceano. In 1420,
Alfonso V of Aragon purchased for 100,000
gold florins the rights of the viscounts of Narbonne. Later, the Aragonese governor,
Leonardo Alagon, rebelled and was also able to beat the king's troops at
Uras in 1470. However, his defeat at the Battle of Macomer in 1478 put a definitive end to the independence of Arborea and of Sardinia as a whole. ==Curatoriae==