Rise of Abu-Abdallah, the Mahdi--His Character and Talents--He rebels against Ali--His Eventful Career--Abd-al-Mumen succeeds Him--Decline of the Almoravide Power in Spain--Raid of Alfonso of Aragon--Rout of Fraga--Death of Alfonso--Indecisive Character of the Campaigns in the War of the Reconquest--Progress of Abd-al-Mumen in Africa--Victories of the Almohades--Natural Hostility of Moor and Berber--Anarchy in the Peninsula--It is invaded by the Africans--Establishment of the Almohade Empire in Andalusia--Almeria taken by the Christians--Its Recapture by the Berbers--Death of Abd-al-Mumen--His Genius and Greatness--Accession of Yusuf--His Public Works--He organizes a Great Expedition--He dies and is succeeded by Yakub--The Holy War proclaimed--Battle of Alarcos--Effects of African Supremacy--Death of Yakub--The Giralda--Mohammed--He attempts the Subjugation of the Christians--Despair of the Latter--Battle of Las Navas de Tolosa--Utter Rout of the Almohade Army 247 CHAPTER XIX THE PROGRESS OF THE CHRISTIAN ARMS General Disorder in the Peninsula--Aggressive Policy of the Christians--Capture of Ubeda--Al-Mamun--Rise of Mohammed-Ibn-Hud--Merida taken by the King of Leon--Prosperity of Barcelona--Jaime I. of Aragon--Siege of Majorca--Terrible Sack of that City--Extinction of the Almohades--Siege and Capture of Cordova by Ferdinand--Valencia surrenders to the King of Aragon--Character of the Struggle between Christian and Moslem--Xativa--Its Prosperity--Murcia becomes the Property of Castile--Xativa acquired by Aragon--Death and Character of Jaime--Rise of the Kingdom of Granada--Its Wealth and Literary Culture--Ferdinand captures Jaen--Mohammed-Ibn-Ahmar, King of Granada, renders Homage to Ferdinand--Seville invested by the Castilians--Great Strength of that City--Its Obstinate Defence--It is reduced by Famine--Character of Ferdinand the Saint 334 CHAPTER XX PROSECUTION OF THE RECONQUEST