A short account of the relations between Islam and Christianity from Muhammad to the Reformation. The author argues that though there were trading and cultural interactions between the two during the period when Arabs controlled most of the Mediterranean world, neither side was remotely interested in the religion of the other. Christian and Moslem lived side by side in a state of mutual religious aversion. Given these circumstances, if religious passions were to be stirred up, confrontation would probably be violent. Fletcher shows how religious misunderstanding and antagonism between the peoples of the book has been present since their earliest encounters.