| Gregorian calendar | 420 CDXX |
| Ab urbe condita | 1173 |
| Assyrian calendar | 5170 |
| Balinese saka calendar | 341–342 |
| Bengali calendar | −174 – −173 |
| Berber calendar | 1370 |
| Buddhist calendar | 964 |
| Burmese calendar | −218 |
| Byzantine calendar | 5928–5929 |
| Chinese calendar | 己未年 (Earth Goat) 3117 or 2910 — to — 庚申年 (Metal Monkey) 3118 or 2911 |
| Coptic calendar | 136–137 |
| Discordian calendar | 1586 |
| Ethiopian calendar | 412–413 |
| Hebrew calendar | 4180–4181 |
| Hindu calendars | |
| - Vikram Samvat | 476–477 |
| - Shaka Samvat | 341–342 |
| - Kali Yuga | 3520–3521 |
| Holocene calendar | 10420 |
| Iranian calendar | 202 BP – 201 BP |
| Islamic calendar | 208 BH – 207 BH |
| Javanese calendar | 304–305 |
| Julian calendar | 420 CDXX |
| Korean calendar | 2753 |
| Minguo calendar | 1492 before ROC 民前1492年 |
| Nanakshahi calendar | −1048 |
| Seleucid era | 731/732 AG |
| Thai solar calendar | 962–963 |
| Tibetan calendar | ས་མོ་ལུག་ལོ་ (female Earth-Sheep) 546 or 165 or −607 — to — ལྕགས་ཕོ་སྤྲེ་ལོ་ (male Iron-Monkey) 547 or 166 or −606 |
Events
By Place
Europe
Asia
- End of the Jin Dynasty in China. Liu Yu (Emperor Wu of Liu Song) is the first ruler of the Song Dynasty.
- Beginning of Southern Dynasties in China.
- Bahram V succeeds Yazdegerd as king of Persia.
Births
- Glycerius, Western Roman Emperor (approximate date)
Deaths
- September 30 - Saint Jerome, translator of the Vulgate
- Orosius, Spanish historian and theologian
- Yazdegerd I of Persia (b. 399)