- Mid-February: Lentienses cross frozen Rhine, invading Roman Empire. Later that year they are defeated by Gratianus
- August 9 - Battle of Adrianople: A large Roman army led by Emperor Valens is defeat by the Visigoths in present-day Turkey. Valens is killed along with 2/3 of his army.
- Gregory Nazianzus ordained bishop of Constantinople
- Theodosius I becomes eastern Roman emperor after the death of Valens
- Roman Emperor Valens (at the Battle of Adrianople)
- Khui Ningomba, Meitei King of Manipur.