| Millennium: | 1st millennium |
|---|---|
| Centuries: | 2nd century – 3rd century – 4th century |
| Decades: | 190s 200s 210s – 220s – 230s 240s 250s |
| Years: | 218 219 220 – 221 – 222 223 224 |
| 221 by topic | |
| Politics | |
| State leaders – Sovereign states | |
| Birth and death categories | |
| Births – Deaths | |
| Establishment and disestablishment categories | |
| Establishments – Disestablishments | |
| Gregorian calendar | 221 CCXXI |
| Ab urbe condita | 974 |
| Armenian calendar | N/A |
| Bahá'í calendar | -1623 – -1622 |
| Bengali calendar | -372 |
| Berber calendar | 1171 |
| Buddhist calendar | 765 |
| Burmese calendar | -417 |
| Byzantine calendar | 5729 – 5730 |
| Chinese calendar | 庚子年十一月二十日 (2857/2917-11-20) — to —
辛丑年十一月三十日(2858/2918-11-30) |
| Coptic calendar | -63 – -62 |
| Ethiopian calendar | 213 – 214 |
| Hebrew calendar | 3981 – 3982 |
| Hindu calendars | |
| - Bikram Samwat | 277 – 278 |
| - Shaka Samvat | 143 – 144 |
| - Kali Yuga | 3322 – 3323 |
| Holocene calendar | 10221 |
| Iranian calendar | 401 BP – 400 BP |
| Islamic calendar | 413 BH – 412 BH |
| Japanese calendar | |
| Korean calendar | 2554 |
| Thai solar calendar | 764 |