Wheatcroft's book provides a detailed history of enmity and hated across the worlds of Christinity and Islam, dating from the seventh century and to the present day. It is a history that is mixed in with legend, jumbling truth with fancifulness and interests with beliefs. The end result is a legacy of reciprocated hatred. The author uses the book to trace the critical junctures which have left a deep impact on the history of relations between the world of Islam and of Christendom, and that allow for an understanding of the history of enmity and hatred which plagues relations between them. Building on these defining junctures and the author's historical view of the relationship between the two sides, and relying on textual sources and imagery, the author manages also to understand the formation of the image of the "infidel" other by the reciprocal groups. In addition to its wide temporal remit, Wheatcroft's book takes in a huge swathe of geography, ranging from the southern edge of Algeria to Vienna in the North, and from the Atlantic Ocean to the Arabian Sea and Indian Ocean, all the while anchoring himself in the Mediterranean basin. Throughout, the question which Wheatcroft asks is how the enmity between these two worlds was created, and how it persisted to this day.