The Kingdom of León

The Vikings invaded Galicia in 844, but were heavily defeated by Ramiro I of Asturias at A Coruña.[42] Many of the Vikings’ casualties were caused by the Galicians’ ballistas – powerful torsion-powered projectile weapons that looked rather like giant crossbows.[42] 70 Viking ships were captured and burned.[42][43] Vikings raided Galicia in 859, during the reign of Ordoño I of Asturias. Ordoño was at the moment engaged against his constant enemies the Moors; but a count of the province, Don Pedro, attacked the Vikings and defeated them.[44]

The Kingdom of León was the strongest Christian kingdom for centuries. In 1188 the first modern parliamentary session in Europe was held in León (Cortes of León). The Kingdom of Castile, formed from Leonese territory, was its successor as strongest kingdom. The kings and the nobility fought for power and influence in this period. The example of the Roman emperors influenced the political objective of the Crown, while the nobles benefited from feudalism.

Petronilla of Aragon and Ramon Berenguer IV, Count of Barcelona.
Muslim armies had also moved north of the Pyrenees but they were defeated by Frankish forces at the Battle of Poitiers, Frankia and pushed out of the very southernmost region of France along the seacoast by the 760s. Later, Frankish forces established Christian counties on the southern side of the Pyrenees. These areas were to grow into the kingdoms of Navarre and Aragon.[45] For several centuries, the fluctuating frontier between the Muslim and Christian controlled areas of Iberia was along the Ebro and Douro valleys.