Traditionally, in the year 312, the Roman emperor Constantine experienced a "vision of the Cross" that led him to convert to Christianity and to defeat his last rival to the imperial throne; and, in 394, a divine wind carried the emperor Theodosius to victory at the battle of the Frigidus River. Other stories heralded the discovery of the True Cross by Constantine's mother, Helena, and the rise of a new kind of miracle-maker in the deserts of Egypt and Syria. These miracle stories helped Christians understand the dizzying changes in their fortunes during the century. They also shed light on Christianity's conflict with other faiths and the darker turn it took in subsequent ages.

In A Century of Miracles, historian H. A. Drake explores the role miracle stories played in helping Christians, pagans, and Jews think about themselves and each other. These stories, he concludes, bolstered Christian belief that their god wanted the empire to be Christian. Most importantly, they help explain how, after a century of trumpeting the power of their god, Christians were able to deal with their failure to protect the city of Rome from a barbarian sack by the Gothic army of Alaric in 410. Augustine's magnificent City of God eventually established a new theoretical basis for success, but in the meantime the popularity of miracle stories reassured the faithful -- even when the miracles came to an end. A Century of Miracles provides an absorbing illumination of the pivotal fourth century as seen through the prism of a complex and decidedly mystical phenomenon.