Kingdom of Aragon (11th – 13th c.)
The Kingdom of Aragon was established in 1035 when the deceased King Sancho III of Navarre left the county of Aragon to his illegitimate son Ramiro I (1035-1063). Ramiro I elevated Aragon into a kingdom and extended Aragonese territory to Sobrarbe and Ribagorza after the death of his half-brother Gonzalo in 1045. His successor Sancho Ramirez (1063-1094) took advantage of the dynastic crisis in the Kingdom of Navarre, captured one third of its territory and added to his title the King of Navarre in 1076.
Aragonese territorial expansion – predominantly on Moorish expense continued during the reign of Peter I (1094-1104) and his successor Alfonso the Battler (1104-1134). The latter tried to gain Castile through marriage with Urraca of Castile (1109-1126) but the royal couple divorced already in 1114. Alfonso was succeeded by his brother Ramiro II (1134-1137) who lost the Kingdom of Navarre which restored its independence on Alfonso’s death in 1134. In 1137, Ramiro II abdicated in favor of Ramon Berenguer IV, Count of Barcelona (1137-1162) who was betrothed to the infant Petronila of Aragon, at the time two years old. The accession of Ramon Berenguer IV to the Aragonese throne established a union between Aragon and Catalonia under one ruling house. The son of Ramon Berenguer IV and Petronila, Alfonso II (1162-1196) inherited both titles King of Aragon and Count of Barcelona. However, Catalonia preserved its own laws and institutions and became the dominant part of the kingdom.