Constantine I the Great

Flavius Valerius Constantinus, known as Constantine I the Great, was Roman emperor in 306–337. He was born at Naissus; his exact birth year is disputed. Following his father Constantius Chlorus’s death, troops proclaimed him emperor at Eboracum in 306. Victory over Maxentius at the Milvian Bridge in 312 secured his western position; victory over Licinius in 324 made him sole ruler.

Constantine continued late Roman administrative and military changes, supported the Christian church and founded a new capital on the site of Byzantium. He was baptised shortly before his death in 337, but his support for Christianity began much earlier. Several Christian traditions later venerated him as a saint. Nicene Christianity acquired a particular state position under Theodosius I in 380, not through a single decision by Constantine.

Before taking the title of Emperor

Maximian became Diocletian’s colleague in 285–286; the Tetrarchy of two Augusti and two Caesars took shape in 293. Constantius Chlorus and Galerius received junior imperial authority. They became Augusti after Diocletian and Maximian abdicated in 305.

Constantine stayed at the eastern court before joining his father in Britain. After Constantius died at Eboracum, modern York, troops proclaimed Constantine Augustus on 25 July 306. Galerius recognised him only as Caesar, giving the senior title to Severus. This was one of the succession disputes that broke down the Tetrarchy.

The Reign of Constantine

Constantine strengthened imperial government, changed military commands and developed court administration. Praetorian prefects gradually acquired predominantly civil duties; the territorial organisation of prefectures developed and changed throughout the fourth century. Taxes and public obligations supported armies and construction, with effects varying by region and legal status.

The gold solidus was an important monetary innovation whose stability had lasting significance. Constantine’s policy cannot be reduced to a single order binding every free farmer to the land.

Ancient accounts of his religious turning point differ. Lactantius connects the events of 312 with a dream and a sign placed on shields; Eusebius describes a heavenly sign and a subsequent dream. These are not independent, photographically exact descriptions. Zosimus later associated conversion with the deaths of Crispus and Fausta in 326, but this does not explain Constantine’s support for Christians before that date.

In 313 Constantine and Licinius agreed on religious liberty and restoration of confiscated Christian property. This agreement is conventionally called the Edict of Milan. Constantine granted privileges to clergy, funded churches and intervened in ecclesiastical disputes. The Donatist conflict was considered at Rome in 313 and Arles in 314; imperial decisions did not end the schism.

In 325 Constantine convened the Council of Nicaea, which condemned Arius’s teaching and adopted a creed. Later policy changes, episcopal restorations and Athanasius’s exile show that controversy continued. Eusebius reports the remark about a “bishop of external affairs” in a different context; it cannot simply be presented as a council speech. Traditional cults continued.

On 11 May 330 the new capital on the site of Greek Byzantium was formally dedicated: Constantinople, also called New Rome. Its position on the Bosporus connected sea and land routes. Constantine expanded the city and its defences, but the famous Theodosian Walls belong to the fifth century. Rome did not lose all its institutions and importance in a single day.

Constantine’s son Crispus and wife Fausta died on his orders in 326. The reasons remain unknown. Later stories of accusations, jealousy and remorse should be distinguished from established circumstances.

The last years of Constantine's reign

In his later years Constantine strengthened his Danubian position. A bridge at Sucidava opened in 328; Romans defeated the Goths in 332 and intervened in a Sarmatian conflict in 334. Ancient reports of hundreds of thousands killed or resettled should not be treated as exact statistics. Settlers could enter military service or receive land under differing conditions, rather than all becoming medieval serfs.

Constantine prepared a campaign against Sasanian Persia but did not carry it out. He fell ill in spring 337 and received baptism from Eusebius of Nicomedia. He died near Nicomedia on 22 May 337 and was buried in the Church of the Holy Apostles at Constantinople.

Results

Constantine transformed relations between imperial authority and the Christian church, while Constantinople became an enduring centre of the eastern Roman state. His administrative, military and monetary measures developed earlier changes. Christian and non-Christian traditions assess him differently; subsequent history cannot be explained by a single model of inevitable decline.

Related topics

• Roman Empire
• Emperors of Rome
• Dominate
• Diocletian

Literature and sources

• Eusebius. Life of Constantine, book IV