The death of Urraca did not end the internal strife in Christian Spain. For ten years there were wars with Teresa and her son Affonso Enríquez of Portugal; there were wars, too, against Aragon and Navarre, following the death of Alfonso the Battler, out of which Alfonso VII procured some extensions of territory. When the century was nearly half gone Alfonso was able to turn energetically to an attack upon the Moslem states, especially between 1144 and 1147 during the second era of the _taifas_. His conquests were vast, but of brief duration, for the Almohades soon entered Spain to deprive him of what he had won. Like Ferdinand I before him Alfonso VII took the title of emperor, which then had a significance equivalent to that of sole temporal ruler of Christendom in succession to the Roman emperors. In the case of Ferdinand and Alfonso it may also have represented a protest against the like pretensions of the Holy Roman Emperors, then reigning principally in Germanic Europe. Alfonso seemed in a fair way to create a peninsula empire, for he was able to make the kings of Aragon and Navarre, the counts of Barcelona and Toulouse, various lesser princes of Spain and southern France, and some rulers of the Moslem _taifas_ swear fealty to him as their feudal sovereign. The imperial confederation had no real strength, however, for the spirit of separatism was as yet too deeply rooted. Alfonso himself demonstrated this by dividing his realm at his death, in 1157, into the two kingdoms of Castile and León. [Sidenote: The defence of Calatrava.] [Sidenote: Alfonso VIII and the overthrow of the Moslems.]