Marianus IV (in Sardinian: Marianu IV de Arbarèe, in Catalan: Marià IV d'Arborea, 1319–1376), called the Great, was the Judge (king) of Arborea, kingdom in the island of Sardinia, from 1347 to his death. He was, as his nickname indicates, the greatest sovereign of Arborea. He was a legislator and a warrior whose reign saw the commencement of massive codification of the laws of his realm and incessant warfare with the Crown of Aragon. He was also a religious man, who had connections to Catherine of Siena. He was, in short, an "wise legislator, able politician, and valiant warrior." Early life in Catalonia Born at Oristano, he was the son of Hugh II and successor of his brother Peter III. At the behest of his father he spent most of his youth in Barcelona, where he was educated at the court of Alfonso IV of Aragon. He participated actively in the coronation of Peter IV in 1336. In 1336 in Barcelona, he married Timbora, daughter of Dalmatius IV of Rocabertí and Beatrice of Serrallonga, Baroness of Cabrenys. In 1339, he was invested by Peter with the counties of Goceano and Marmilla, in Sardinia. In 1347, the Doria rebelled and defeated the Catalans at Aidu de Turdu, occupying Bonorva. This sparked a long war between Aragon and Genoa, but at the outset the Doria could not take advantage of their victory. On 11 September 1349, he returned to Oristano, two years after succeeding his childless elder brother. One of his first acts was to repopulate the town of Goceano, rebuild the castle there, and plant a florid garden. War with Aragon Though an alliance had been in effect with Aragon for more than fifty years at the time of his accession, Marianus realised that the political aim of Peter IV was nothing less than the annexation of Sardinia and, following the conquest of Alghero (1353), he parted ways with the Catalans. He allied with the Genoese and the Doria, then at war with Aragon, and made himself an enemy of the Aragonese. Marianus' first directive was against Gherardo della Gherardesca, a loyal Pisan vassal of the Aragonese. He attacked Castel di Castro from the south but was rebuffed. He initiated a siege until his Doria allies could attack from the north. They did, and took Alghero. His armies proved successful in the field and he succeeded in expelling the Aragonese from