The Crown of Aragon (in Aragonese: Crown d'Aragón; in Catalan: Crown d'Aragó) is also known by other alternative names. It was including to the set of territories that were submitted to the jurisdiction of the king of Aragon, from year 1164 until 1707.
     On November 13, 1137, Ramiro II El Monje, king of Aragon, deposited in his son-in-law Ramón Berenguer the kingdom (although not the king's dignity), signing this in ahead like Count of Barcelone and Prince of Aragon. Petronila took the title of "Queen of Aragon" and Ramón Berenguer took the name of prince and sovereign of Aragon. According to some modern historians, the marriage was done under the form of "Marriage in House". This supposes that, having not hereditary male, the husband fulfills the government function, but not that of head of the house, which will only be granted to the heir, although does not exist historiographical consensus on this matter. In 1164, Alfonso II de Aragon would inherit the joint patrimony.
      Later, for conquests of new territories and for marriage, this union of kingdom and county in only one crowns, would extend the historical territories of the Aragon and Catalonia, up to including other domains: fundamentally the kingdoms of Majorca, Valencia, Sicily, Corsica, Sardinia and Naples, as well as the duchies of Athens (from 1331 to 1388) and Neopatria (between 1319 and 1390).
      With the wedding of Reyes Católicos in 1469, the convergence process begins with the Crown of Castile, forming the base of what would become in the Crown of Spain, although the different kingdoms would preserve its legal systems and characteristics. With the Decrees of Nueva Planta of 1705-1716, Felipe V eliminates finally most of these privileges and jurisdictions.
     The name of «Crown of Aragon» is applied in the current historiography from the dynastic union between the Kingdom of Aragon and the County of Barcelone; although was not used historically up to the reign of Jaime II the Just. At the end of the XIIIth century, and between the XIIth century and the XIVth the expression most extended to refer to the domains of the king of Aragon was that of «Casal d'Aragó -Country house d'Aragó-».
     The formation of the Crown, therefore, has its origin in the dynastic union between the kingdom of Aragon and the county of Barcelone.
     After the death without descent of Alfonso El Batallador -the year 1134, during the Fraga siege- his testament was transferring his kingdoms to the military orders of the Saint Sepulcro, of the Hospital of Jerusalem and of the Templars. Before this unusual fact, the inhabitants of Navarre, which in that moment was part of the possessions of the king of Aragon, proclaimed king to García V Ramírez and were separated definitely of Aragon.

     In this context, the Aragonese noblemen did not accept the testament and nominated new king Ramiro II the Monk, Alfonso's brother and that was at that time bishop of Roda-Barbastro. Before this situation, Alfonso VII of Castile took advantage to claim succession rights on the throne of Aragon, while García V was showing his aspirations and the Pope was demanding the fulfillment of the testament.
      The pretensions of Castile were creating a problem for the count of Barcelone, Ramón Berenguer, since were coinciding with the rivalry between the county and the kingdom of Aragon, for the conquest of the Moslem grounds of the faction of Lerida. The king of Castile Alfonso VII made clear his intentions when in December, 1134 penetrated with a bold expedition in Saragossa and made to flee to Ramiro. Nevertheless, these facts did not end up by being favorable to the aspirations of the Castilian king, who finally should resign from his pretensions on the Aragonese kingdom. For his part, Ramiro II, in spite of his ecclesiastic's condition, married Inés de Poitiers; marriage of that had a daughter -Petronila- in 1136. It was having to plan the future marriage of the girl, what supposed choosing between the Castilian dynasty or the of Barcelone one.



     The county of Barcelone, in that epoch, was in hands of Ramón Berenguer IV. Previously, already he had consolidated his supremacy on other Catalan counties like Osona, Gerona or Besalú. At the same time, there had been revealed the potentiality of the Catalan fleet, with facts like the momentary conquest of Majorca (1114) or the expeditions carried out by the counts of Barcelone in grounds mulberries of Valencia, being frustrated their intentions by the intervention of Castile, personified by Alfonso VI and the Cid (defeat of Berenguer Ramón the Fratricidal in the Tévar battle). At the same time, beyond the Pyrenees some alliances politics was initiating that would culminate in the union of Barcelone and Provence for the wedding of Ramón Berenguer III with Dulce de Provenza.