| Millennium: | 1st millennium BC |
|---|---|
| Centuries: | |
| Decades: | |
| Years: |
| 90 BC by topic |
| Politics |
|---|
| Categories |
| Gregorian calendar | 90 BC XC BC |
| Ab urbe condita | 664 |
| Ancient Egypt era | XXXIII dynasty, 234 |
| - Pharaoh | Ptolemy X Alexander, 18 |
| Ancient Greek era | 172nd Olympiad, year 3 |
| Assyrian calendar | 4661 |
| Balinese saka calendar | N/A |
| Bengali calendar | −682 |
| Berber calendar | 861 |
| Buddhist calendar | 455 |
| Burmese calendar | −727 |
| Byzantine calendar | 5419–5420 |
| Chinese calendar | 庚寅年 (Metal Tiger) 2608 or 2401 — to — 辛卯年 (Metal Rabbit) 2609 or 2402 |
| Coptic calendar | −373 – −372 |
| Discordian calendar | 1077 |
| Ethiopian calendar | −97 – −96 |
| Hebrew calendar | 3671–3672 |
| Hindu calendars | |
| - Vikram Samvat | −33 – −32 |
| - Shaka Samvat | N/A |
| - Kali Yuga | 3011–3012 |
| Holocene calendar | 9911 |
| Iranian calendar | 711 BP – 710 BP |
| Islamic calendar | 733 BH – 732 BH |
| Javanese calendar | N/A |
| Julian calendar | N/A |
| Korean calendar | 2244 |
| Minguo calendar | 2001 before ROC 民前2001年 |
| Nanakshahi calendar | −1557 |
| Seleucid era | 222/223 AG |
| Thai solar calendar | 453–454 |
| Tibetan calendar | 阳金虎年 (male Iron-Tiger) 37 or −344 or −1116 — to — 阴金兔年 (female Iron-Rabbit) 38 or −343 or −1115 |
Year 90 BC was a year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Caesar and Lupus (or, less frequently, year 664 Ab urbe condita) and the Third Year of Zhenghe. The denomination 90 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.