ナバス・デ・トロサの戦い
In 1212, the Almohad Caliph Muhammad 'al-Nasir' (1199–1214), the successor of al-Mansur, after an initially successful advance north, was defeated by an alliance of the four Christian kings of Castile, Aragón, Navarre, and Portugal, at the Battle of Las Navas de Tolosa in the Sierra Morena. The battle broke the Almohad advance, but the Christian powers remained too disorganized to profit from it immediately.