The Arch of Constantine A gilded coffin, draped in purple silk, stood in the center of the audience chamber. Around the casket, hundreds of candles sent streamers of smoke heavenward, and dozens of courtiers did their level best to weep. With a rustle of leather and the rasp of hobnails, a young man in gilded armor led a small troop of palace bodyguards into the room. Reflections gliding over the burnished marble floor, the soldiers slid carrying poles through the coffin’s base, and lifted it with creaking armor and infinite ceremony. Then, led by the golden-armored prince, they processed through the door and into the sunlit courtyard. The courtiers, following the coffin, adjusted their cloaks; the morning, chilled by a breeze off the Sea of Marmora, was cool for June. Spear tips glittered and togas fluttered in the breeze as the procession made its unwieldy way down the colonnaded central avenue of Constantinople. It halted before the gleaming façade of the recently-completed Church of the Holy Apostles. The honor guard was dismissed, and replaced by a group of bishops in black vestments, who carried the coffin into the church. There, beneath a gilded ceiling, the coffin was lifted onto a candle-studded dais before the altar. The service commenced; and after the Archbishop Alexander had delivered a long eulogy praising the wisdom and piety of the dead emperor, the coffin was carried into a circular mausoleum adjoining the church. In the echoing interior, where clerestory windows checkered the marble floor with light, a colossal porphyry sarcophagus waited. Six marble cenotaphs carved with the names of the Apostles were arrayed among the columns on either side. A golden cross glittered in the cupola. The emperor’s coffin was lowered into the sarcophagus; the two-ton lid was levered shut; and so, sometime in the first week of June, AD 337, Flavius Valerius Constantinus, emperor of the Romans and defender of the Christian faith, was laid to rest. When Constantine had been proclaimed emperor thirty years before, perhaps 10% of the Roman Empire’s population was Christian. Most Christians then lived in the cities of the Greek-speaking eastern provinces, where – by imperial edict – they were being savagely persecuted. Few could have imagined that the Roman Empire would be governed by a Christian within a few years, or that a majority of the Empire’s population would convert within the century. To understand Constantine’s career and the emergence of a Christian Roman Empire, we need to briefly survey what came before: polytheism, and the crisis of the third century. Before the spread of Christianity, most inhabitants of the Roman Empire practiced religions that were polytheistic and essentially local in character. There were a few common points of reference, most notably the Greco-Roman Pantheon (that is, Jupiter and friends), and the imperial cult. But every city and village had its own temples, traditions, and gods. Even the Roman state religion was really just a city cult blown up to gargantuan proportions. Although religion permeated daily life, it tended to be conceptualized less as a source of universalizing ethical codes than in terms of time-honored rituals and lived practice. There were of course exceptions to these bald generalizations. Certain cults – most famously, the Eleusinian Mysteries of Demeter and Kore – appealed to men and women from across the Mediterranean, promising a blessed afterlife alien to most local traditions. New proselytizing religions like Mithraism and Manicheism, moreover, spread widely through the Empire, creating communities that bridged traditional regional and social divides. The most prominent outlier was Judaism. The Romans always regarded Jewish monotheism as something of a curiosity; but it was never persecuted, even after the Roman-Jewish Wars. The historical heart of Judaism was of course in Palestine; but by the time of the Roman conquest, large Jewish communities existed in virtually every sizeable city in the eastern Mediterranean. Rome itself had no fewer than eleven synagogues. The Jews of the Diaspora spoke Greek as their first language, and often participated fully in the political and cultural life of their polytheistic neighbors. In fact, considerable numbers of polytheists, intrigued by the ethical dimension of Judaism, either converted outright or affiliated themselves with the synagogues as God-fearers. In was in this milieu that Christianity first spread. Initially, Christianity was regarded by the Roman government – and indeed by many Christians – as a sect of Judaism. By the early second century, however, it was clear that Christianity was a distinctive, and rapidly growing, religion. A few governors and city councils organized regional suppressions of the church in the ensuing decades; but the first general persecution did not take place until the mid-third century, when the emperor Decius ordered every Roman citizen to offer sacrifice for the safety of the Empire. Decius took this unprecedented step in response to the crises of the mid-third century. Since the end of the Severan Dynasty twenty years before, the Empire had lurched from disaster to disaster: emperor after emperor had been assassinated, frontier after frontier had collapsed, and the value of the currency had spiraled ever downward. With the benefit of hindsight, we can see that this crisis originated in a failure of central authority. Since no emperor had the time, luck, or talent to establish a lasting dynasty, the only way to seize and hold power was to buy the loyalty of the troops with ever-higher pay – a policy that destroyed both the prestige of the emperorship and the value of the currency. The situation was exacerbated by invasion on multiple fronts. First, in the 220s, the Parthian Arsacid Dynasty – Rome’s punching bag for centuries – was replaced by the much more aggressive and efficient Sassanid Dynasty, which invaded and briefly conquered the provinces of Mesopotamia and Syria. Although the Romans wrested back their lost territory, the Sassanids remained a thorn in the Empire’s side. In the same years as the Sassanid incursion into Syria, a new threat – the Goths – appeared on the Danube frontier. This tribal confederacy exploited Roman disarray to raid deeply into the Balkans, reducing vast tracks of the frontier provinces to a smoldering wasteland. To counter the enemies that beset the Empire on every side, emperors gave increasing authority to provincial governors. Though often successful in the short run, this policy sometimes encouraged the most powerful and efficient governors to declare themselves emperor. The Roman Empire, in short, was tottering in the mid-third century, and Decius thought that only a return to ancestral tradition and worship could save it. He never imagined that the Christians – by now a sizeable minority in many eastern cities – would refuse to sacrifice on religious grounds. But on encountering resistance, he ordered provincial governors to enforce the decree. Some did so zealously, executing Christians who refused to sacrifice as traitors to the Empire. Fortunately for the church, however, the persecution was short-lived; Decius marched against the Goths and, at the catastrophic Battle of Abritus, was trapped in a swamp and killed along with most of his army. The crisis deepened in the following decades. The Goths returned, ravaging cities in Greece and Asia Minor; the Sassanids captured Antioch, the third city of the Empire; and for years, nearly half the provinces were in the hands of rebel governors. From the 270s onward, however, disaster was averted by a series of tough and competent soldier-emperors. The first of these, Aurelian, reunited the Empire, drove back the invaders on all sides, and built the great wall that still encircles Rome. The greatest of the reformers, however, was Diocletian, who reigned from 284 to 305. Diocletian was a superb organizer. To increase revenue, he regularized taxation, sidestepping the ongoing problem of inflation by allowing payments in kind. To ensure effective administration, he subdivided the provinces and greatly enlarged the bureaucracy. And to end the civil wars and succession crises that had troubled the Empire for so many years, he created the Tetrarchy, a college of four emperors. In this system, the two senior emperors, with the title of Augustus, would make the two junior emperors – or Caesars – their heirs; when a senior emperor died or retired, a junior emperor would take his place, and select a trusted comrade as the new junior emperor. As his co-emperors, Diocletian chose three experienced fellow-generals: Maximian, Galerius, and Constantius. Appointing himself senior emperor of the east, he made Maximian senior emperor of the west. Galerius served as Diocletian’s junior emperor, and Constantius as Maximian’s. Each of the tetrarchs was made responsible for a cluster of provinces, and based in a city near a troubled frontier – a policy that ensured constant surveillance of Rome’s enemies. Having stabilized the frontiers and regularized the imperial succession, Diocletian set out to promote the unity and loyalty of his subjects. Like most Romans, he understood moral decline as the fundamental cause of the Empire’s woes; and as a staunch traditionalist, he sought to use the ancient state cults of the Roman religion as a means of rectifying the problem. On coins and in rituals, he associated himself with Jupiter, king of the gods. He promoted the restoration of ancient temples and festivals. He ordered the leaders of the Manicheans – a dualistic religion that originated in Persia – to be burned alive atop their scriptures. And he began to consider how he might eradicate the greatest threat to traditional religion: the rapidly-growing Christian church. Early in 303, Diocletian and his co-emperors published an edict ordering all churches to be destroyed, all Christian scriptures to be collected and burnt, and all Christian meetings to cease.