821
| Years: 817 818 819 820 – 821 – 822 823 824 825 | |
| Decades: 790s 800s 810s – 820s – 830s 840s 850s | |
| Centuries: 8th century – 9th century – 10th century | |
Events
- Tang Mu Zong becomes emperor of China
Births
Deaths
- February 11 – Benedict of Aniane, monastic founder and saint
- December 18 – Theodulf, Bishop of Orléans
- Coenwulf, king of Mercia
Categories: 821