| Millennium: | 1st millennium BC |
|---|---|
| Centuries: | |
| Decades: | |
| Years: |
| 46 BC by topic |
| Politics |
|---|
| Categories |
| Gregorian calendar | 46 BC XLVI BC |
| Ab urbe condita | 708 |
| Ancient Egypt era | XXXIII dynasty, 278 |
| - Pharaoh | Cleopatra VII, 6 |
| Ancient Greek era | 183rd Olympiad, year 3 |
| Assyrian calendar | 4705 |
| Balinese saka calendar | N/A |
| Bengali calendar | −638 |
| Berber calendar | 905 |
| Buddhist calendar | 499 |
| Burmese calendar | −683 |
| Byzantine calendar | 5463–5464 |
| Chinese calendar | 甲戌年 (Wood Dog) 2652 or 2445 — to — 乙亥年 (Wood Pig) 2653 or 2446 |
| Coptic calendar | −329 – −328 |
| Discordian calendar | 1121 |
| Ethiopian calendar | −53 – −52 |
| Hebrew calendar | 3715–3716 |
| Hindu calendars | |
| - Vikram Samvat | 11–12 |
| - Shaka Samvat | N/A |
| - Kali Yuga | 3055–3056 |
| Holocene calendar | 9955 |
| Iranian calendar | 667 BP – 666 BP |
| Islamic calendar | 688 BH – 686 BH |
| Javanese calendar | N/A |
| Julian calendar | 46 BC XLVI BC |
| Korean calendar | 2288 |
| Minguo calendar | 1957 before ROC 民前1957年 |
| Nanakshahi calendar | −1513 |
| Seleucid era | 266/267 AG |
| Thai solar calendar | 497–498 |
| Tibetan calendar | 阳木狗年 (male Wood-Dog) 81 or −300 or −1072 — to — 阴木猪年 (female Wood-Pig) 82 or −299 or −1071 |
Year 46 BC was the last year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Consulship of Caesar and Lepidus (or, less frequently, year 708 Ab urbe condita). The denomination 46 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.
This year marks the change from the pre-Julian Roman calendar to the Julian calendar. The Romans had to periodically add a leap month every few years to keep the calendar year in sync with the solar year but had missed a few with the chaos of the civil wars of the late republic. Julius Caesar added Mercedonius (23 days) and two other intercalary months (33 and 34 days respectively) to the 355-day lunar year, to recalibrate the calendar in preparation for his calendar reform, which went into effect in 45 BC.[1][2][3] This year therefore had 445 days, and was nicknamed the annus confusionis ("year of confusion") and serves as the longest recorded calendar year in human history.[4] The actual planetary orbit-year remained the same.