SHADOW LINE:

Islam, Holland argues, was not born fully formed with the Prophet as he received God's revelation in a cave in 610, or when he fled Mecca for Medina around 622. In fact, the religion took nearly two centuries to assume its present form: a strict monotheism supremely loyal to the memory and teachings of its founder, Mohammed, governed by the words of its sacred text, the Koran, and overseen by an alliance of zealous princes and powerful priests.

During those two centuries, Islam and the caliphs took on board almost everything that had been integral to the success of the other emerging faiths and empires of the age: Persian Zoroastrianism, the Christianity of the eastern Romans and Judaism, which lacked a territorial empire but endured by the potency of its teaching throughout Palestine, Arabia and beyond.

From these old models, the Arab conquerors who rode out of the desert to seize North Africa, most of the Iberian Peninsula, the Holy Land, the fertile crescent and virtually everything between the Aral and Arabian seas, gleaned the means by which they, too, could rule the world.

Theologically, this meant the potency of submission to a single God; the doctrinal power of a single, perfect messenger to whom God had revealed himself; the relentless persecution of deviant or cultish forms of religious belief; and, most importantly of all, the enduring reach of a sacred text.

Practically, it suggested other methods to control a wide and variegated people: a legal code in which believers held privileged status; the exultation of warriors who fought in the name of the Almighty; spectacular buildings raised to the glory of God; and the conscious mythologising of great cities as the central hubs of both political power and pilgrimage. (Jerusalem and Constantinople pre-empted Mecca, Medina and Baghdad.) 

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