When the Arab invasion took place, the Roman Hispanics, who were used to live under foreign domination for almost a milennium, and a part of the Visigothics who stayed in those terrtories, adapted themselves to the new situation without any major problems, since the Arabs treated them with great tolerance and they even in some cases became enjoying an important share of power, as are the cases of the Gothic count Teodomiro in Murcia and the family Banu Qasi in Zaragoza (whose name comes from Casius,the noble Gothic who submitted before the caliph al-Walid). He embraced Islam under his protection and kept command of the lands he governed in the name of king Rodrigo. This situation of tolerance prevailed for almost 150 years. A number of Christians, the so called muladíes, attracted by a superior culture and a much more pleasant style of life, became to arabize themselves and converted to Islamism, which also brought them fiscal privileges. Another important part of Christians, the so called Mozarabics, kept clung to their own customs, culture and religion within this permissive environment; although they were not allowed to build new churches, they were entitled to keep the existing ones int the seventh century.

It is interesting to point out in this period not only an important influence of the Islamic culture on the Christians that lived in their territory, but also the influence of the Spanish culture on the new conquerors, although this aspect has not been analysed in depth. In fact, the Muslim art in Spain contains important elements inherited from the Roman and Visigothic architecture. One of the most meaningful examples is the Mosque of Córdoba that started to be built in 785 upon the Visigothic cathedral of San Vicente, of which we know that many of its elements were reutilized and that we can find in its structures architectural solutions already existing in Spain, like the horseshoe arch or the utilization of series of arches placed on top, very similar to the Roman aqueduct of Merida, for instance.

But two facts provoked a radical change in the situation of Christians in Al-Andalus:

• By the year 850 an increasingly conversion, willingly or not, of a part of Christians to Islamism and their assimilation to that society, due to new pressures but also to the attractiveness that the Arabic culture had from an intelectual as well as from a material standpoint, started to poison the relationship between Arabs, Muladíes and Mozarabics which ended by generating a violent reaction in the most orthodox Mozarabic faction. Led by Álvaro, a layman, probably of Jewish origin, and Eulogio, a clerk who became bishop of Toledo; both highly cultured; they left an important set of literary works of religious subject; generated a violent reaction among Christians who manifested their will to keep their identity in front of the increasing arabization that was taking place. An important group of Mozarabic led by San Eulogio, did not hesitate to become martyred if that meant the strengthening of the religious faith of their fellow Christians. Despite the extraordinary Council summoned in Córdoba by Abd-er-Rahman the second in 852, in an attempt to prevent the madness of public martyrdom of Christians, these did not change their attitude, that, besides generating around 50 martyrs in less thay ten years, enormously complicated the coexistence between Arabs and Christians. At the same time it awoke in Asturias the interest of what was going on there, in open expansion under the reign of Alfonso III el Magno, and in the Carolingian Empire, with big interests in the Marca Hispánica (Spanish March) that would later become Barcelona.

• In the second half of the ninth century, within a context of uprisings and tensions in the emirate, emerges Omar ben Hafsum, a muladí, son of Hafs -i.e., Alfonso- who heads an uprising against the emirate of Córdoba in the highlands of Antequera and Ronda and founds an independent kingdom with its capital Bobastro. After converting to Christianism, he manages to keep an independent kingdom for more than 50 years until after his death it was reconquered by Abd al-Rahman the third (912-961) in 928 (Among the ruins of Bobastro there is the only Mozarabic church known in Al-Andalus, on top a nearly inaccessible peak)

These facts provoked an important change in the situation of Mozarabic in Al-Andalus and favoured the emigration of an important number of people towards the Christian territories, in the areas recently occupied by León and Castille, in particular, north of the Duero river, taking along with them the best heritage of the Visigothic culture that they had kept so fervently for a century and a half, and the cultural heritage that had been brought to Spain by the Arabs.

Meanwhile, the kingdom of Asturias is rapidly expanding in the north. In the year 910, Ordoño the second moves his court to León, better situated than Oviedo, to rule the territories conquered by his father, Alfonso II el Magno (866-910), who in his forty-three years of reign he gave the definite impulse toward the Reconquest, expanding the conquest boarder till the Duero river, resettling with people coming from his reigns as well as with Mozarabics, founding villas and monasteries, protecting them with fortified cities like Oporto, Toro, Zamora Simancas or Dueñas, and creating the basis of the future Castille by building the fortress of Burgos. In the political area, he had united through matrimony with the royal family of Navarra and he gave a great impulse to recover all of Spain uniting the different Christian kingdoms under one "Magnus Imperator", as his sons called him. Along this same line, he was a great supporter of culture and promoted the construction of civil works, especially in Oviedo and León, as well as churches and monasteries.

He generated a movement usually called "Mozarabic Art", that from our point of view, once we explain describing its main characteristics, it should be considered as "Neo-Visigothic". He accomplished this within an environment of development of the kingdom by resettling new territories, creating new towns and founding new monasteries, in some cases upon the ruins of some that existed before the Arab invasion; the arrival of important groups of Mozarabics, many of them monks, that brought along a Visigothic heritage, keenly kept through very difficult circumstances, and enriched with new knowledge learnt from the Arabs, coexisting with the new settlers that came from the northern territories in a monarchy that self declared itself as a continuation of the Visigothic kingdom of Toledo, and also with a cultural sediment that, although very different in its architecture, was also based on the Visigothic culture.

The situation in the Marca Hispánica was also different. It stayed for very few years under the Arabs. Pepino el Breve had already expelled them from the Visigothic Septimania in 759 and Luis el Piadoso definitely took over Barcelona from the Arabs in 801 with an army of Spanish Christians that had fled to France from Al-Andalus. During all this period when the Mozarabic Art develops, Cataluña (a name that had not yet strated to being used), carried on being the set of counties that extended at both sides of the Pyrenees, depending from the Carolingian Empire with capital in Narbona: although as of 1000 the counts started to enjoy a relative independence. As a consequence, constructions pass from Visigothic to Mozarabic almost without a continuity solution and it is very difficult to precise in a large number of small rural churches that have survived, whether they are from the Visigothic period, old Visigothic constructions rebuilt later, or new constructions of what has been called Mozarabic Art.

Another fact to bear in mind in this area is the influence of the Carolingian art in the most important buildings of those times. The Carolingian art had two basic styles in religious constructions. The main examples of one is the Capilla Palatina de Aquisgrán, that imitates the Byzantine style of San Vital de Rávena. The main example of the other style is the church that Teodulfo built in Germiny-des-Prés. He had emigrated from Spain and became one of the most influential characters in Carlomagno's reign (768-814), under the name of Píndaro, and bishop of Orleans. The style that had a greater influence in Catalonia was the latter one, where we find a clear relationship with the Visigothic architecture, both for its structure as well as for the type of construction and the utilization of the horseshoe arch.

The reult of all of these circumstances is that at the beginning of the tenth century, the Marca Hispánica went also through an expansion process, protected from the Arabs by the Carolingian Empire and with an important rise of the artistic development which main sources are found in the Visigothic seventh century.