Centuries: 3rd century - 4th century - 5th century
- 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.
- Pope Damasus I is accused of adultery but is exonerated by emperor Gratian.
- Siyah K'ak' begins to replace Mayan kings with relatives of Spearthrower Owl, emperor of Teotihuacan.
- Germanus of Auxerre, bishop of Auxerre