[Sidenote: Inter-relations of the Christian and Moslem peoples.] Except in times of war, relations between the Christian and Moslem peoples were even cordial and intimate. They visited one another’s countries, aided one another in civil wars, engaged in commerce, and even contracted mixed marriages, not only among people of the lower classes, but also among those of the highest rank, even to that of royalty. Mohammedan law did not require the conversion of Christian wives, but many of the latter embraced the Moslem faith, with the consent, too, of their families. Although there were instances of Mohammedan women marrying Christians, the reverse was usually the case, for the conquerors did not bring their families as had the earlier Germanic invaders. Religious differences were not an insuperable barrier in this period: there was scarcely a war confined to Christians on the one side and Mohammedans on the other; the Mozárabes were not greatly molested within the Moslem state; Christians were often employed in administrative capacities by the emirs and caliphs; and Christian mercenaries, many of them Spaniards, fought in the Moslem armies. It was only natural, therefore, that the neighboring Arabic civilization should have exercised not a little influence on Christian Spain, especially since the power and wealth of the caliphate were so much greater than in the kingdoms of the north. In intellectual aspects--for example, in philosophy and science--the Arabic influence was to be greater at a succeeding time, but in political and military matters and in language much passed over to the Christians in this period. In like manner the Spanish peoples reacted upon the invaders, but this was confined principally to the effects produced by the Renegados and Mozárabes, whose contributions were largely due to the conditions of the Moslem world in which they lived. [Sidenote: Diversity in Christian Spain.] Christian Spain itself was far from being a unit; rather diversity was the rule. The northwest followed the Visigothic tradition, while the north centre and northeast, especially Navarre and Catalonia, while retaining much of the Visigothic institutions came into frequent contact with French peoples, who gave a new turn to their civilization. Within each section, too, there were many complex differences between one region and another. Hence the institutions of the principal areas may be taken separately. _Kingdoms of Asturias, León, and Castile_ [Sidenote: Social classes in the Christian northwest.]