Balearic Islands having partitioned his domains between his sons in his will. The will created a new Kingdom of Mallorca from the Balearic islands and the mainland counties of Roussillon or Montpellier, which was left to his son James II. However, the terms of the will specified that the new kingdom be a vassal state to the Kingdom of Aragon, which was left to his older brother Peter. Chafing under the vassalage, James joined forces with the Pope Martin IV and Philip III of France against his brother in the Aragonese Crusade, leading to a 10-year Aragonese occupation before the islands were
Balearic Islands declined between 2007 and 2017 while the largest-increasing populations were the Moroccans, Italians, and Romanians. Each one of the three main islands is administered, along with its surrounding minor islands and islets, by an insular council ("consell insular" in Catalan) of the same name. These four insular councils are the first level of subdivision in the autonomous community (and province) of the Baleares. Before the administrative reform of 1977, the two insular councils of Ibiza and Formentera were forming in a single one (covering the whole group of the Pitiusic Islands). This level is further subdivided into six comarques only