- Louis II succeeds Lothair as western emperor. Two other sons, Lothair and Charles, also get parts of the kingdom.
- Succession of Pope Benedict III (855 - 858). Anastius is made anti-pope by Lothair.
- Ethelwulf, king of Wessex and Bretwalda, abdicates in favor of his son Ethelbald.
- Ethelwulf grants the English churches the right to receive tithes.
- Edmund becomes king of East Anglia.