Mapping the PastMAP 9.1 The Expansion of Islam, 622–900 The rapid expansion of Islam in a relatively short span of time testifies to the Arabs’ superior fighting skills, religious zeal, and economic ambition as well as to their enemies’ weakness. Plague, famine, and political troubles in Sassanid Persia contributed to Muslim victory there.ANALYZING THE MAP Trace the routes of the spread of Islam by time period. How fast did it spread? How similar were the climates of the regions that became Muslim?CONNECTIONS Which were the most powerful and populous of the societies that were absorbed into the Muslim world? What regions or societies were more resistant?