| Millennium: | 2nd millennium |
|---|---|
| Centuries: | |
| Decades: | |
| Years: |
| 1231 by topic |
|---|
| Leaders |
| Birth and death categories |
| Births – Deaths |
| Establishments and disestablishments categories |
| Establishments – Disestablishments |
| Art and literature |
| 1231 in poetry |
| Gregorian calendar | 1231 MCCXXXI |
| Ab urbe condita | 1984 |
| Armenian calendar | 680 ԹՎ ՈՁ |
| Assyrian calendar | 5981 |
| Balinese saka calendar | 1152–1153 |
| Bengali calendar | 638 |
| Berber calendar | 2181 |
| English Regnal year | 15 Hen. 3 – 16 Hen. 3 |
| Buddhist calendar | 1775 |
| Burmese calendar | 593 |
| Byzantine calendar | 6739–6740 |
| Chinese calendar | 庚寅年 (Metal Tiger) 3928 or 3721 — to — 辛卯年 (Metal Rabbit) 3929 or 3722 |
| Coptic calendar | 947–948 |
| Discordian calendar | 2397 |
| Ethiopian calendar | 1223–1224 |
| Hebrew calendar | 4991–4992 |
| Hindu calendars | |
| - Vikram Samvat | 1287–1288 |
| - Shaka Samvat | 1152–1153 |
| - Kali Yuga | 4331–4332 |
| Holocene calendar | 11231 |
| Igbo calendar | 231–232 |
| Iranian calendar | 609–610 |
| Islamic calendar | 628–629 |
| Japanese calendar | Kangi 3 (寛喜３年) |
| Javanese calendar | 1140–1141 |
| Julian calendar | 1231 MCCXXXI |
| Korean calendar | 3564 |
| Minguo calendar | 681 before ROC 民前681年 |
| Nanakshahi calendar | −237 |
| Thai solar calendar | 1773–1774 |
| Tibetan calendar | 阳金虎年 (male Iron-Tiger) 1357 or 976 or 204 — to — 阴金兔年 (female Iron-Rabbit) 1358 or 977 or 205 |
Year 1231 (MCCXXXI) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar.