Centuries: 3rd century - 4th century - 5th century
- January 19 - Theodosius I is elevated as Roman Emperor at Sirmium.
- September 13 - Nun Yax Ayin becomes king of Tikal.
- Ardeshir II becomes King of Persia.
- Gratianus refuses title of eastern Roman Emperor.
- War of Feishui in China.
- Theodosius I makes peace with king Fritigern of the Visigoths.
- Celtic village of Cularo renamed Gratianopolis, later becomes Grenoble.
- Settlement of Jew Town in India by Jews.
- Niall becomes King of Ireland.
- Gregory Nazianzus becomes Patriarch of Constantinople, and is wounded when he is attacked by a mob of heretics.