On this day, December 25, in medieval history:
- 800 – Charlemagne crowned Holy Roman Emperor
- 875 – Charles the Bald crowned Holy Roman Emperor by Pope John VIII
- 1066 – William the Conqueror crowned King of England at Westminster Abbey in London
- 1085 – William the Conqueror commissions the creation of the Domesday Book
- 1100 – Baldwin I crowned King of Jerusalem