Emperor · 272 – 337
Constantine the Great
Key Takeaways
- Constantine was the first Roman emperor to convert to Christianity.
- His Edict of Milan ended the persecution of Christians in the empire.
- He founded Constantinople as a new imperial capital.
- He convened the Council of Nicaea to settle Christian doctrine.
Constantine the Great made two decisions that changed the course of history: he embraced Christianity, and he built a new capital in the East. Together they reshaped Rome, Europe and the future of the Western world.
The first Christian emperor
According to tradition, before the Battle of the Milvian Bridge in 312 AD, Constantine saw a Christian sign in the sky and won under its protection. The next year his Edict of Milan ended the persecution of Christians, and he favored the faith for the rest of his reign, even convening the Council of Nicaea to settle its doctrine.
A new Rome
In 330 AD Constantine founded Constantinople on the Bosphorus — a new, Christian capital that would outlast Rome itself by a thousand years as the heart of the Byzantine Empire. Reuniting the empire under his sole rule, this emperor of late antiquity set in motion a Christian Roman world later inherited by rulers like Justinian I and, in the West, Charlemagne.
Reunited the Roman Empire under his sole rule, legalized Christianity through the Edict of Milan, convened the Council of Nicaea, and founded Constantinople, setting the course for a Christian Roman and Byzantine world.
Military Feats
- Won the Battle of the Milvian Bridge, reportedly under a Christian sign, in 312 AD.
- Reunited the divided Roman Empire under his sole rule.
Political Achievements
- Issued the Edict of Milan granting tolerance to Christianity.
- Founded Constantinople as a new Christian capital.
- Convened the First Council of Nicaea in 325 AD.
Historical influence score: 87/100
Influence
Constantine's embrace of Christianity and founding of Constantinople redirected the course of Western and Eastern history, linking the Roman state to the Christian Church.
Legacy
He set Europe on its path to becoming Christian and founded the city that would anchor the Byzantine Empire for a thousand years.
Little-Known Facts
- He is said to have seen a Christian sign in the sky before the Battle of the Milvian Bridge.
- He was baptized only on his deathbed, a common practice in his era.
Myths & Misconceptions
Did Constantine make Christianity the state religion?
Not quite — he legalized and favored Christianity, but it became the official religion of the empire only later, under Theodosius I.
Connections
Frequently Asked Questions
Who was Constantine the Great?
Constantine the Great (272–337 AD) was the Roman emperor who first embraced Christianity, ended its persecution, and founded Constantinople.
Why is Constantine important?
He transformed the Roman Empire by legalizing Christianity and founding Constantinople, decisions that shaped the Christian and Byzantine worlds for over a thousand years.
Citations & Sources
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