In our supposedly secular age governed by reason and technology, fundamentalism has emerged as an overwhelming force in every major world religion. Why? This is the fascinating, disturbing question that bestselling author Karen Armstrong addresses in her brilliant new book The Battle for God. Writing with the broad perspective and deep understanding of human spirituality that won huge audiences for A History of God, Armstrong illuminates the spread of militant piety as a phenomenon peculiar to our moment in history. Contrary to popular belief, fundamentalism is not a throwback to some ancient form of religion but rather a response to the spiritual crisis of the modern world. As Armstrong argues, the collapse of a piety rooted in myth and cult during the Renaissance forced people of faith to grasp for new ways of being religious—and fundamentalism was born. Armstrong focuses here on three fundamentalist movements: Protestant fundamentalism in America, Jewish fundamentalism in Israel, and Islamic fundamentalism in Egypt and Iran—exploring how each has developed its own unique way of combating the assaults of modernity. Blending history, sociology, and spirituality, The Battle for God is a compelling and compassionate study of a radical form of religious expression that is critically shaping the course of world history.