By the will of Sancho the Great of Navarre, Castile had become legally a kingdom in 1035. Ferdinand I (1035-1065) soon overwhelmed the king of León, uniting all northwestern Spain under his rule. Wars with Navarre followed until 1054, after which Ferdinand devoted himself with great religious zeal to campaigns against the Moslem _taifas_, making numerous conquests, and subjecting many states to the payment of tribute. Despite the lesson of his own experience he divided his realm, at death, into the three kingdoms of Castile, León, and Galicia, besides two lesser principalities. A long civil war followed, out of which there emerged Alfonso VI (1065-1109) as sole ruler of the domain of his father. Alfonso VI took up the wars against the Moslems with great success, and on one occasion, in 1082, was able to ride his horse into the sea in the extreme south of Spain at Tarifa, when he is said to have exclaimed: “This is the last land in Spain, and I have trod it.” The principal event of the reign was the capture of Toledo in 1085. Alfonso had promised to restore the _taifa_ king of Toledo to his throne, from which he had been ousted by a rebellion, but changed his mind, and took the city for himself. From that time forward Toledo was of great military importance to the Christians, serving as the centre of the reconquest, and it was also the medium through which Moslem civilization began to produce an effect on Castile. The treaty of capitulation was not very faithfully carried out; for example, Alfonso had promised to allow the Mohammedans to retain their principal mosque for purposes of worship, but in his absence the monks of Cluny were able to persuade the queen to take over that edifice as a Christian church. The incident is illustrative of a new crusading spirit which had entered Spain with the monks of Cluny, although it had not yet become general. _Taifa_ after _taifa_ now humbled itself before Alfonso; Valencia was captured, and the former king of Toledo became its nominal ruler, but with a Castilian army; and Alfonso could with reason entitle himself “sovereign of the men of the two religions,” a phrase which shows that Christian zeal was not altogether uncompromising. It was then that the Almoravide invasion checked the Castilian king, but although he lost Valencia he was able to maintain the principal part of his conquests. [Sidenote: The Cid.]