Years afterward constantine remembered the battle at the Milvian Bridge as the moment when he had first used a military standard constructed in the shape of a cross. Before the battle, he claimed, both he and his army had witnessed a vision of the cross in the sky, and Jesus Christ himself had appeared in a dream to explain the vision and direct him to build a battle standard. In his Life of Constantine Eusebius subsequently embedded those memories in a religious context and transformed the vision and the battle into moments of conversion to Christianity, of the emperor personally and of the empire in general. In this process of remembering and recording, however, both emperor and bishop had furthermore tried to forget someone else. During the battle outside Rome another emperor had also been present. But when Maxentius had fallen into the Tiber River, he had at the same time slipped into oblivion.

Constantine's memories and Eusebius' reinterpretation of those memories have set the tone for modern scholarship too, and overlooking Maxentius has reinforced the notion that the battle was all about Constantine and Christianity. In contrast, focusing on Maxentius offers an opportunity to avoid highlighting Christianity. The confrontation between these two emperors instead emphasized other consequential trends. One concerned the orientation of the Roman empire. Maxentius symbolized the conventional importance of Rome as the capital, while Constantine represented the increasing significance of frontier zones, in particular in the north along the Rhine and the Danube.

After analysis and interpretation, a new narrative. So far, however, this critique of ancient accounts of the battle at the Milvian Bridge has challenged the expectation of a new master narrative of the battle and its consequences in two related ways.

One is the emphasis on the constructed nature of the early accounts of the battle and its aftermath. The anonymous orator of 313, the designers and sculptors of the arch at Rome, the rhetorician Lactantius, the bishop Eusebius, the poet Porfyrius, the panegyrist Nazarius, and Constantine himself all had their own agendas, which they could promote through the medium of discussing the battle or the emperor's vision. For modern historians one important implication of this focus on the construction of ancient texts should not be simply a reverse emphasis on deconstruction, as if it were possible, through careful scrutiny, to find true details or an accurate basic framework behind the ancient authors' agendas. Too often positivism is hypercritical and hypercredulous at the same time. Instead, the lesson should be the realization that our modern narratives are likewise constructed. We historians need to acknowledge that we are both scholars, reading and interpreting ancient texts, and authors, writing and constructing new texts.

The second challenge to writing a new narrative is chronology, or rather, the direction of the chronology. So far the discussion in this book has proceeded essentially backward, starting with modern scholarship, withdrawing to medieval and Byzantine perspectives and then to historical accounts derived from some of the earlier accounts, retreating to very early accounts, and finally examining some of the immediate reactions.

Eusebius' account of constantine's vision and dream before the battle at Rome in his Life of Constantine has become powerfully influential among modern historians. This is an odd outcome. Eusebius was still revising Life when he died probably in May 339, more than twenty-five years after the battle. He was the bishop at Caesarea in Palestine and hence knew little about events at distant Rome. He clearly used his biography of the emperor to promote a theological and political agenda about the nature of Christian emperorship. Late, far away, sectarian, partisan: Eusebius' account should have struggled to become so significant.

The redeeming factor of his account of the vision and the dream was the declaration that he had heard it directly from Constantine himself. Eusebius claimed to be recording the memories of an eyewitness. But this assertion in turn raises another set of issues about the dating of Constantine's recollections, the reliability of Eusebius' reporting, and the accuracy of his interpretations. Constantine recalled his memories for Eusebius and other bishops for specific reasons at a specific moment long after the battle; Eusebius subsequently recorded the emperor's stories for different reasons at a different moment after the emperor's death. The account of the emperor's vision and dream in Life hence represented three distinct layers of particular circumstances: Eusebius' remembrance of Constantine's memories of events from long ago.

His horse is spooked and rears back, but constantine looks up. A radiance brightens his face, and he raises his hands in admiration. Perhaps he is praying.

We visualize the moment of Constantine's vision of the cross in the sky as just such a spectacular epiphany because we have already seen Bernini's luminous marble statue of the emperor astride his horse. During the mid-seventeenth century successive popes hired the gifted sculptor and artist Gian Lorenzo Bernini to complete the new Church of St. Peter in the Vatican. In addition to his grand decoration of the interior, Bernini designed semicircular colonnades to embrace the vast elliptical piazza in front of the church. He also added an oversize statue of Constantine, located in a niche at the juncture between the corridor from the north colonnade and the front portico of the church. In contrast to earlier equestrian statues that had commemorated the generic majesty of emperors, this statue portrayed a precise dramatic moment, “the very turning point of Constantine's life, an instant when the emperor was himself subjected to a superior power.” As a result, the installation of the statue in this church seemed to link Constantine's vision with the defense of Christianity and, more specifically, with the enhancement of the power of the popes.

Later historians and churchmen were keen to requisition and exploit the episode of Constantine's vision of the cross. Another episode with obvious potential for reassessment was his baptism.

A book about memories of Constantine is also an album of memories for me. Earlier versions of parts of chapters were presented as the Moritz Lecture at Kalamazoo College, a plenary lecture at the annual conference of the North American Patristics Society, and a lecture at Calvin College. The most rewarding moments of those occasions were always the complementary conversations: with Anne Haeckl, John Wickstrom, and their students at Kalamazoo College; with Paul Blowers, Virginia Burrus, Elizabeth Digeser, David Hunter, Adam Schor, and Dennis Trout at NAPS; and with Young Kim, Mark Williams, and their students at Calvin College.

As an undergraduate and a graduate student I was blessed to enjoy the company and learning of wonderful professors. As a professor I continue to learn from the undergraduates in my survey courses and the graduate students in my seminars, who have become my most invigorating teachers. After his victory at the Milvian Bridge, the emperor Constantine relished arguing with bishops at their councils. He would likewise have enjoyed talking about late antiquity with Alex Angelov, Jon Arnold, and Rob Chenault, and with Ian Mladjov, who designed and drew the splendid maps.

Stimulating comments from Mark Humphries and the anonymous Press readers were helpful, encouraging, and much appreciated. Publishing with Cambridge University Press is a high honor; working with Beatrice Rehl, the best editor in academic publishing, is a delightful pleasure.

The stories about the emperor's vision and dream before the battle outside Rome were Constantine's own memories. Distinguishing those stories from the commentary in which Eusebius subsequently embedded them in Life of Constantine has interesting implications. One is that it is possible to detect some of the influences that independently shaped Constantine's memories and Eusebius' commentary. Although the memories and the commentary converged in Eusebius' Life, until that moment they had followed separate tracks. The emperor's memories and the bishop's commentary each had a distinct backstory.

After the battle and his return to Gaul early in the following year, Constantine remained in the western provinces. He continued to campaign along the Rhine frontier; he returned to Rome in 315; and after seizing the Balkans from Licinius, he campaigned along the Danube frontier. The backstory for his memories hence included his subsequent experiences in the West, as well as various accounts of the battle that he heard, read, or viewed (Chapters 6–7). In contrast, the backstory for Eusebius' commentary in Life consisted largely of his own earlier accounts. For modern historical analysis, disentangling these earlier accounts becomes an opportunity to see Eusebius at work as a historian and an apologist. His narrative in Life of Constantine's victory at Rome was not his first account of the battle. Nor was it his second account. In fact, it was not even his third account.

Knowledge about events in western provinces was not common in eastern provinces. At Athens, Praxagoras composed his “History of Constantine the Great” in two volumes, apparently soon after the emperor's death. Because Praxagoras wrote his history as a young man while only in his early twenties, he had been born after the battle at the Milvian Bridge. According to a short summary of his now-lost history, Constantine had once lived at Diocletian's court at Nicomedia, and the emperor Galerius had plotted against him. After Constantine fled to his father in Britain, he became an emperor and organized an army of “Celts and Germans.” According to Praxagoras, Constantine was upset on hearing that Maxentius was mistreating the people of Rome. In the subsequent military campaign “Constantine was victorious in battle and turned [Maxentius] to flight. While he was fleeing, Maxentius experienced a reversal in his life [and the] treachery that he had contrived for his enemies: he fell into a trench he had himself dug. Some of the Romans cut off his head, hung it on a pole, and walked around in the city.”

Praxagoras next described Constantine's victory over Licinius at Nicomedia, his consolidation of imperial rule, and his foundation of a new capital at Byzantium. He was clearly quite impressed by the emperor's “virtue, excellence, and total good fortune.” But by highlighting these activities in the East, he imposed an overall eastern perspective on the significance of Constantine's reign.