| Millennium: | 1st millennium BC |
|---|---|
| Centuries: | 3rd century BC – 2nd century BC – 1st century BC |
| Decades: | 150s BC 140s BC 130s BC – 120s BC – 110s BC 100s BC 90s BC |
| Years: | 126 BC 125 BC 124 BC – 123 BC – 122 BC 121 BC 120 BC |
| 123 BC by topic | |
| Politics | |
| State leaders – Sovereign states | |
| Birth and death categories | |
| Births – Deaths | |
| Establishments and disestablishments categories | |
| Establishments – Disestablishments | |
| Gregorian calendar | 123 BC |
| Ab urbe condita | 631 |
| Armenian calendar | N/A |
| Bahá'í calendar | -1966 – -1965 |
| Bengali calendar | -715 |
| Berber calendar | 828 |
| Buddhist calendar | 422 |
| Burmese calendar | -760 |
| Byzantine calendar | 5386 – 5387 |
| Chinese calendar | [[Sexagenary cycle|]]年 (2514/2574) — to —
[[Sexagenary cycle|]]年(2515/2575) |
| Coptic calendar | -406 – -405 |
| Ethiopian calendar | -130 – -129 |
| Hebrew calendar | 3638 – 3639 |
| Hindu calendars | |
| - Bikram Samwat | -66 – -65 |
| - Shaka Samvat | N/A |
| - Kali Yuga | 2979 – 2980 |
| Holocene calendar | 9878 |
| Iranian calendar | 744 BP – 743 BP |
| Islamic calendar | 767 BH – 766 BH |
| Japanese calendar | |
| Korean calendar | 2211 |
| Thai solar calendar | 421 |