The tenth century dawned in violence and disorder. Charlemagne's empire was in ruins, most of Spain had been claimed by Moorish invaders, and even the papacy in Rome was embroiled in petty, provincial conflicts. To many historians, it was a prime example of the ignorance and uncertainty of the Dark Ages. Yet according to historian Paul Collins, the story of the tenth century is the story of our culture's birth, of the emergence of our civilization...