The History of the Medieval WorldIn her earlier work, The History of the Ancient World, Susan Wise Bauer wrote of the rise of kingship based on might. But in the years between the fourth and twelfth centuries, rulers had to find new justification for their power, and they turned to divine truth or grace to justify political and military action. Right began to replace might as the engine of empire. Not just Christianity and Islam but also the religions of the Persians, the Germans,