| Millennium: | 1st millennium |
|---|---|
| Centuries: | 8th century – 9th century – 10th century |
| Decades: | 800s 810s 820s – 830s – 840s 850s 860s |
| Years: | 835 836 837 – 838 – 839 840 841 |
| 838 by topic | |
| Politics | |
| State leaders – Sovereign states | |
| Birth and death categories | |
| Births – Deaths | |
| Establishment and disestablishment categories | |
| Establishments – Disestablishments | |
| Gregorian calendar | 838 DCCCXXXVIII |
| Ab urbe condita | 1591 |
| Armenian calendar | 287 ԹՎ ՄՁԷ |
| Bahá'í calendar | -1006 – -1005 |
| Bengali calendar | 245 |
| Berber calendar | 1788 |
| Buddhist calendar | 1382 |
| Burmese calendar | 200 |
| Byzantine calendar | 6346 – 6347 |
| Chinese calendar | 丁巳年十二月初二日 (3474/3534-12-2) — to —
戊午年十二月十一日(3475/3535-12-11) |
| Coptic calendar | 554 – 555 |
| Ethiopian calendar | 830 – 831 |
| Hebrew calendar | 4598 – 4599 |
| Hindu calendars | |
| - Bikram Samwat | 894 – 895 |
| - Shaka Samvat | 760 – 761 |
| - Kali Yuga | 3939 – 3940 |
| Holocene calendar | 10838 |
| Iranian calendar | 216 – 217 |
| Islamic calendar | 223 – 224 |
| Japanese calendar | |
| Korean calendar | 3171 |
| Thai solar calendar | 1381 |