The newly-created kingdom of Portugal, established by the military powers of Alphonso, was soon at war with that of Leon.[5] Aragon and Castile, after many bloody quarrels, united in a league against Navarre. Sancho VIII., the sovereign of that little state, was forced to resort to Africa for assistance, and implore the aid of the Almohades. But they, being but recently established on the throne of Morocco, were still employed in exterminating the dismembered fragments of the party of the Almoravides, and could not, in spite of their eager desire to do so, establish any claim to their assumed rights in Spain. Nevertheless, two kings of the race of the Almohades, both named Joseph, passed the Mediterranean more than once with numerous armies. The one was successfully opposed by the Portuguese, and did not survive his final defeat; the other was more fortunate, and succeeded in vanquishing the Castilians, but {100} was soon after obliged to accept a truce and return in haste to Morocco, to which new disturbances recalled him, A.D. 1195, Heg. 591. But these useless victories, these ill-sustained efforts, did not permanently disable either the Mussulmans or the Christians. On both sides, the vanquished parties soon re-entered the field, in utter neglect of the treaties into which they might ever so recently have entered. The sovereigns of Morocco, though regarded as the kings of Andalusia, nevertheless possessed only a precarious authority in that country, which was always disputed when they were absent, and acknowledged only when necessity forced the Mussulman inhabitants to have recourse to their protection. At last Mohammed _El Nazir_, the fourth prince of the dynasty of the Almohades, to whom the Spaniards gave the name of the Green, from the colour of his turban, finding himself in quiet possession of the Moorish empire of Africa, resolved to assemble all his forces, to lead them into Spain, and to renew in that country the ancient conquests of Tarik and Moussa. A holy war was proclaimed, A.D. 1211, Heg. 608, and an innumerable army {101} crowded around the ensigns of Mohammed, left the shores of Africa under the guidance of that monarch, and safely arrived in Andalusia. There their numbers were nearly doubled by the Spanish Moors, whom hatred to the very name of Christian, arising from the vivid remembrance of accumulated injuries, induced to join the bands of El Nazir. The sanguine Mohammed promised an easy triumph to his followers, together with the certainty of rendering themselves masters of all that their ancestors had formerly possessed; and, burning to commence the contest, he immediately advanced towards Castile at the head of his formidable army, which, according to the reports of historians, amounted to more than six hundred thousand men.