After the celebration of his Vicennalia, Diocletianus had left for Ravenna. The emperor was now in his sixties and his health was not good. At the start of the year 304 he nevertheless became consul for the ninth time, together with Maximianus, who was now consul for the eighth time. Diocletianus probably knew it would be his last consulship, if indeed the previous year he and Maximianus had agreed that both emperors would abdicate on 1 May 305. Diocletianus left Ravenna again and headed for his capital in Asia Minor, the city of Nicomedia. Because of his bad health, the emperor had to be carried in a litter. In Nicomedia he would take important decisions about the future of the Tetrarchy. These decisions differed markedly from the agreements that had previously been reached and put severe pressure on the system with two senior and two junior emperors. And then there was the problem with the Christians that the emperor so far had failed to solve.
The final edict
Around February of the year 304, Diocletianus issued the fourth edict against the Christians while on his way to his capital. The first edict had basically deprived Christians of their rights and had introduced structural discrimination. The second had ordered the arrest of Christian leaders, while the third had arranged for a general amnesty, provided that the clergymen were willing to sacrifice first. The fourth edict strengthened that provision by ordering Roman citizens throughout the Empire to sacrifice to the gods or to their emperor. Those who refused to participate faced the death penalty or a lifetime of forced labour in the mines. The edict has often been compared to the edict that the emperor Decius had issued over half a century previously, and rightly so. However, the edict seems to have remained largely unknown in the western part of the Roman Empire. In the east, its enforcement was left to the provincial governors, who acted quite arbitrarily. And so the edict was mostly enforced in Syria, Palestine (Caesarea) and Egypt, and in parts of North Africa. Not surprisingly, these were also the regions that had the largest Christian communities.
We do not know how many people lost their lives as a result of Diocletianus’ persecutions. Estimates vary from a few hundred to many thousands. In his work on the martyrs of Palestine and in his Church History, Eusebius of Caesarea mentions the names of several martyrs. Some of these he had known personally, and of others he had very likely witnessed the execution. There can be little doubt that their stories are authentic. It is furthermore fairly certain that the fourth edict had a deep impact in Egypt. In the Egyptian provinces many Christians were willing to die for their faith, while at the same time the Roman authorities were determined to suppress their activities. Diocletianus himself had set an example in 297 when he had massacred many citizens in Alexandria, thus emulating the atrocities committed by Caracalla in 215.
In North Africa, which was part of Maximianus’ territories, a number of Christians were martyred as well. In 304 bishop Felix of Thibiuca, mentioned in a previous post, and the 49 martyrs of Abitinae met their tragic ends. Once again the Roman governors in this part of the Empire were prepared to act ruthlessly. In a way the bishop of Rome, Pope Marcellinus (296-304), was victim of the persecutions as well. He had almost certainly handed over sacred texts to the authorities to be burned. Other Christians had blamed him bitterly for that and had even spread the rumour that he had sacrificed to the traditional gods. Although according to later stories the pope had apologised for his deeds and had even died as a martyr, it is not inconceivable that Marcellinus was simply deposed by the Christian community of Rome. The circumstances of his death will probably remain shrouded in mystery forever, but it is a fact of history that Marcellinus’ successor as bishop of Rome, Pope Marcellus, was not elected until 308 (see Rome: San Marcello al Corso).
Although Diocletianus’ persecutions must have at least claimed several hundreds of Christian lives, there can be no doubt that in later centuries dozens of martyrs were venerated whose historicity is doubtful and who cannot with certainty be considered victims of Diocletianus or the other Tetrarchs. What to think of Saint Pancratius of Rome for instance, who was said to have been decapitated along the Via Aurelia? What to think of Saint Anastasia of Sirmium, whose feast day is 25 December, or of the Sicilian martyr Saint Vitus? And then there are the soldier Saint Antoninus, patron saint of Piacenza, the soldiers Felix and Fortunatus, who are venerated in Vicenza, and Saint Justina of Antioch, who was reportedly murdered in Nicomedia on the orders of Diocletianus himself. Perhaps Marcellinus, Petrus, Tiburtius and Gorgonius were historical figures, but even though Pope Damasus (366-384) was convinced they were, we know nothing about their lives.
Until relatively recently, Diocletianus was still seen as the Great Persecutor of Christians. The famous church of Santa Maria degli Angeli e dei Martiri from the sixteenth century, built into the baths of Diocletianus in Rome, is co-dedicated to the Christian martyrs who had supposedly worked on these baths as forced labourers. Undoubtedly slaves were used for this project, but the 40,000 Christian labourers from the Christian tradition are pious nonsense. The fact that so many martyrs are attributed to the persecutions instigated by Diocletianus probably says more about this emperor’s reputation among Christians than about his actual involvement in the deaths of all the aforementioned martyrs.
In the meantime, Diocletianus’ health was failing rapidly. According to Lactantius the caesar Galerius took advantage of this situation by visiting the old augustus in Nicomedia and pressuring him to accept a different arrangement for the succession within the Tetrarchy. Not Constantine, son of the caesar Constantius, and Maxentius, son of the augustus Maximianus and Galerius’ son-in-law, were to become the new caesares, but two other figures. These were his friend Flavius Valerius Severus and his nephew Maximinus Daza, the son of his sister. Given the close (familial) ties between these men and Galerius, it is likely that he played a large role in drafting the new arrangement and in suggesting alternative successors. Apparently he preferred a good friend and a kinsman over a son-in-law. Diocletianus, for his part, may have preferred Maximinus Daza because the man had displayed a clear hatred of Christians, which made him a useful person for continuing the persecutions in the east. Lastly, Diocletianus may have had second thoughts about an arrangement that would see Constantius become augustus in the west and his son Constantine caesar in the east. That would lead to a risky culmination of power.
In the end it must have been Diocletianus, who kept a clear mind until his death at the end of 311, who made the decision. Around March of the year 305 he decided what the succession arrangement within the Tetrarchy would look like. The new arrangement was written down and sent to Maximianus in Mediolanum (Milan). On 1 May of that same year, the two augusti abdicated simultaneously, one Nicomedia, the other in Mediolanum. Diocletianus must have felt nothing but relief, but Maximianus had abdicated with great reluctance. Constantius and Galerius became the new augusti, the former adding Spain to his territories, the latter Asia Minor. Severus was appointed the new caesar in the west under Constantius and Maximinus Daza began serving as the new caesar under Galerius in the east. Tired, but no doubt with a sense of fulfilment, Diocletianus withdrew to his palace in Salonae (Split), where he spent his days growing cabbage. Maximianus left for Lucania in Southern Italy. The Roman Empire would hear from him again, and from his son Maxentius, who for the moment bided his time on his estate just outside Rome.
And how did Constantine fare, who had also been kicked out of the Tetrarchy? He was still serving under Galerius and was given permission by the new augustus to travel to his father, the other augustus. According to Constantine himself, his departure from Nicomedia was basically an escape. He supposedly left the city before Galerius would change his mind and kept a watchful eye especially while travelling through Severus’ territories, afraid that the caesar would see him as a rival for the throne and kill him. The historians Zosimus and Aurelius Victor claim that Constantine hamstrung or killed all the available horses at the stopovers, so that no one would be able to pursue him. There can be little doubt that the future emperor greatly exaggerated his adventures. What is furthermore certain, is that he arrived safely in Augusta Treverorum (Trier), and from there took the road to Gesoriacum (Boulogne). In Gesoriacum Constantine probably met with his father Constantius, who was about to cross over to Britannia for a campaign against the Picts. The Roman world would hear a lot more from Constantine as well.
- Aurelius Victor, De Caesaribus 39-40 (translated and annotated by H.W. Bird);
- Lactantius, De mortibus persecutorum, chapters XVIII-XIX;
- Zosimus, Historia Nova, Book 2.
- Adrian Goldsworthy, The Fall of the West, p. 174-176;
- Henk Singor, Constantijn, p. 199-211;
- Timothy Venning, A Chronology of the Roman Empire, p. 636-638.
 Henk Singor, Constantijn, p. 200.
 Henk Singor, Constantijn, p. 169.
 Timothy Venning, A Chronology of the Roman Empire, p. 637.
 Lactantius, De mortibus persecutorum, chapters XVIII-XIX.
 Alternatively known as Daca (Epitome de Caesaribus 40.18) or Daia (in Lactantius’ work).
 Zosimus, Historia Nova, Book 2.8; Aurelius Victor, De Caesaribus 40.