Alfonso was a dignified and somewhat enigmatic figure. His rule was characterised by the renewed supremacy of the western kingdoms of Christian Hispania over the eastern (Navarre and Aragón) after the reign of Alfonso the Battler. He also sought to make the imperial title meaningful in practice, though his attempts to rule over both Christian and Muslim populations was even less successful. His hegemonic intentions never saw fruition, however. During his tenure, Portugal became de facto independent, in 1128, and was recognized as de jure independent, in 1143. He was a patron of poets, including, probably, the troubadour Marcabru.
When Alfonso the Battler, King of Navarre and Aragón, died without descendants in 1134, he willed his kingdom to the military orders. The aristocracy of both kingdoms did not accept this and García Ramírez, Count of Monzón was elected in Navarre while Alfonso pretended to the throne of Aragón. The nobles chose another candidate in the dead king's brother, Ramiro II. Alfonso responded by occupying La Rioja, conquering Zaragoza, and governing both realms in unison. From this point, the arms of Zaragoza began to appear in those of León.
In several skirmishes, he defeated the joint Navarro-Aragonese army and put the kingdoms to vassalage. He had the strong support of the lords north of the Pyrenees, who held lands as far as the River Rhône. In the end, however, the combined forces of the Navarre and Aragón were too much for his control. At this time, he helped Ramon Berenguer III, Count of Barcelona, in his wars with the other Catalan counties to unite the old Marca Hispanica.
In 1135, Alfonso was crowned "Emperor of All the Spains" in the Cathedral of León. By this, he probably wished to assert his authority over the entire peninsula and his absolute leadership of the Reconquista. He appears to have striven for the formation of a national unity which Hispania had never possessed since the fall of the Visigothic kingdom. The elements he had to deal with could not be welded together. The weakness of Aragon enabled him to make his superiority effective, although Afonso I of Portugal never recognised him as liege, thereby affirming Portugal's independence. In 1143, he himself recognised this status quo and consented to the marriage of Petronila of Aragon with Ramon Berenguer IV, a union which combined Aragon and Catalonia into the Crown of Aragon.
. . . early in the morning the castle was surrendered and the towers were filled with Christian knights, and the royal standards were raised above a high tower. Those who held the standards shouted out loud and proclaimed "Long live Alfonso, emperor of León and Toledo!"
In 1144, Alfonso advanced as far as Córdoba. Two years later, the Almohads invaded and he was forced to refortify his southern frontier and come to an agreement with the Almoravid Ibn Ganiya for their mutual defence. When Pope Eugene III preached the Second Crusade, Alfonso VII, with García Ramírez of Navarre and Ramon Berenguer IV, led a mixed army of Catalans and Franks, with a Genoese-Pisans navy, in a crusade against the rich port city of Almería, which was occupied in October 1147. It was Castile's first Mediterranean seaport. In 1151, Alfonso signed the Treaty of Tudilén with Ramon Berenguer. The treaty defined the zones of conquest in Andalusia in order to prevent the two rulers from coming into conflict. Six years later, Almería entered into Almohad possession. Alfonso was returining from an expedition against them when he died in pass of Muradel in the Sierra Morena, possibly at Viso del Marqués (Ciudad Real).
Alfonso also had two mistresses, having children by both. By an Asturian noblewoman named Guntroda Pérez, he had an illegitimate daughter, Urraca (1132-1164), who married García Ramírez of Navarre, the mother retiring to a convent in 1133. Later in his reign, he formed a liaison with Urraca Fernández, widow of count Rodrigo Martínez and daughter of Fernando García of Hita, an apparent grandson of García Sánchez III of Navarre, having a daughter Stephanie 'the Unfortunate' (1148-1180), who was killed by her jealous husband, Fernan Ruiz de Castro.
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