Originally West African, Berber nomads, the Almoravids emerged from what is today Mauritania to rule Morocco, western Algeria, and Muslim Spain. Over the course of the century-long lifespan of the Almoravid dynasty, the concept of jihad evolved through four distinct phases: a struggle for righteousness, a war against pagans in the Sahara to impose their own sense of righteousness, war against "bad" Muslims in Sijilmasa and the rest of the Maghrib, and finally, war against Christian infidels--the Christian kings of Iberia.