In this groundbreaking book, Selina O'Grady examines how and why the post-Christian and the Islamic worlds came to be as tolerant or intolerant as they are. She asks whether tolerance can be expected to heal today's festering wound between these two worlds, or whether something deeper than tolerance is needed. Told through contemporary chronicles, stories and poems, Selina O'Grady takes the reader through the intertwined histories of the Muslim, Christian and Jewish persecutors and persecuted. From Umar, the seventh century Islamic caliph who laid down the rules for the treatment of religious minorities in what was becoming the greatest empire the world has ever known, to Magna Carta John who seriously considered converting to Islam; and from al-Wahaabi, whose own brother thought he was illiterate and fanatical, but who created the religious-military alliance with the house of Saud that still survives today, to Europe's bloody Thirty Years war that wearied Europe of murderous inter-Christian violence but probably killed God in the process. This book is an essential guide to understanding Islam and the West today and the role of religion in the modern world.