Alfonso II inherited Catalonia in 1162, and became king of Aragon proper in 1164 on the abdication of Petronilla. Later he inherited nearly all of southern France. He was also a frequent ally of Alfonso VIII of Castile against the Moslems, gaining some territories on his own account. In 1179 these two kings made a treaty dividing Spain between them, fixing the limits of their respective present and future conquests,--a noteworthy instance of the approach toward the unification of Spain. Alfonso II was succeeded by Pedro II “the Catholic” (1196-1213) at a time when affairs were in a critical state in his French dominions. That region had been in constant turmoil, as a result both of the ambitions of the kings of France and of the comparative independence and selfish aims of the feudal lords. There was now added a new factor,--the widespread Albigensian heresy, which had been accepted by the majority of the Provençal people and even more by their lords. With matters in this state Pedro visited Rome in 1204, and, while there, gave his dominions in vassalage to the pope, receiving them back as a fief. This act was to have important consequences at a later time, but if its immediate object was to check French pretensions to southern France, as has been supposed, it was not very successful, for the pope himself proclaimed a crusade against the Albigenses. The crusaders were French nobles, who represented a purely French invasion quite as much as they did an orthodox host. Under their leader, Simon de Montfort, they won several victories, displaying such cruelty against Catholics and heretics alike that they were censured by a famous religious at that time preaching among the Albigenses, Domingo de Guzmán. Guzmán was the Spaniard who later founded the Dominican order, named for him, and who became canonized as Saint Dominic (San Domingo). Pedro II endeavored to mediate to check the temporal designs of Montfort, but was persuaded by the pope to recognize the French leader as his vassal in the regions he had conquered. When Montfort continued in his aggressive designs Pedro II declared war against him, but was defeated in a battle which cost him his life. [Sidenote: Early years of the reign of Jaime “the Conqueror.”]