We have rapidly grown used to the idea, particularly since the declaration of a world-wide war on terrorism, that between Islam and the West there exists a deep historical and ideological gulf. Christopher Walker's book turns such accepted views on their head and paints instead a picture of two belief systems which have a long history of toleration and mutual influence. When Islam first appeared in the seventh century it did not appear to be radically different from Christianity. Bede noted the coming of the Saracens without rancour and Offa, king of Mercia in the eighth century, adopted the gold dinar of Baghdad as his currency. In the Tudor period, Elizabeth I's positive relations with the Ottoman Porte led to a near-alliance between Protestantism and Islam. Sultan Murad III addressed her majesty as 'most sapient princess of the magnanimous followers of Jesus ...' Now the politicization of Islam and its association with nations reforming themselves after the colonial shifts of both World Wars has led to a polarization dormant since the Crusades. Is there, asks Christopher Walker, a way back from the brink? Will we ever experience again an inclusive and accepting worldview?