The history of Islam in Europe is an important, but often neglected era. David Lewis, the author of God's Crucible, obviously has command of the subject matter, but he presents this knowledge in a disorganized manner. He repeatedly and abruptly jumps back and forth in the timeline and geographic location. For instance, the second to the last chapter ends with the last battle in Spain between Christians and Muslim, while then the very first sentence of the last chapter asks a rhetorical question about ninth-century Baghdad!