In 897 C.E. the corpse of the recently deceased Pope Formosus was unearthed, propped on a throne and tried for heresy in Rome. The motives had less to do with theology than naked secular politics, writes Paul Collins as he shines a lantern into the Dark Ages. Whether or not Collins is correct in naming the 10th century as the significant turning point for Western Civilization, he uncovers many fascinating details. Rome barely withstood a seaborne attack by Muslims and one band of Arabs, marooned on a mountain near Turin, converted to Catholicism. Their descendants live in a village called Saracinesco whose current mayor bears a family name derived from his Arab ancestry Dell'Ali.