Centuries: 8th century - 9th century - 10th century
- Ethelred succeeds as king of Wessex (or 866).
- Ragnar Lodbrok invades England, but is defeated by king Ella of Northumbria
- A Russian expedition for the first time threatens Constantinople.
- Louis the German divides his kingdom among his sons.
- Lothair, threatened with excommunication, takes back his first wife,