4th century
What happened around the world
Europe
- 313 Edict of Milan — Constantine and Licinius end the persecution of Christians
- 330 Founding of Constantinople — Constantine moves the capital to the Bosporus for 1,000 years
- 365 Crete earthquake and tsunami — A tsunami tosses Alexandria's ships onto rooftops
- 395 Division of the Roman Empire — East and West part ways: one falls, the other lasts 1,000 years
Middle East
- c. 301 Armenia adopts Christianity — Tiridates III makes Christianity the religion of his realm
- 325 First Council of Nicaea — Bishops condemn Arianism and adopt the Nicene Creed
- c. 337 Georgia adopts Christianity — Tradition credits a captive woman preacher, Saint Nino
Africa
- c. 330 Aksum adopts Christianity — King Ezana puts the cross on Aksum's coins
Asia
- c. 320 Founding of the Gupta Empire — Chandragupta I opens the golden age of northern India
- 399–412 Faxian's pilgrimage to India — A monk in his sixties walks from China to India
Americas
- 378 Teotihuacan intervention at Tikal — A Teotihuacan general reshapes Tikal and its dynasty
Who ruled
- China: dynasties
- Jin 266 – 420
- India: empires
- Gupta Empire 320 – 550
- Rome and Byzantium
- Constantine the Great 284 – 395, Western Empire 395 – 476
Largest states
- Roman Empire
- Sasanian Empire
- Western Jin
- Eastern Roman Empire
- Gupta Empire
- Western Roman Empire
- Former Qin
- Huns
- Eastern Kushans
- Northern Wei
- Kidarites
- Later Zhou
- Western Satraps
- Former Yan
- Indo-Sasanian Empire
- Protectorate of the Western Regions
- Vakataka Kingdom
- Later Zhao
- Former Zhao
- Gothia
- Later Qin
- Kingdom of Kush
- Tuyuhun
- Kingdom of Armenia
- Later Yan
- Xionites
- Cheng Han
- Vandals
- Goguryeo
- Kingdom of Axum
- Mayan City-States
- Himyarite Kingdom
- Former Liang
- Late Pallava Empire