Year 400 BC was a year of the pre-Julian Roman calendar. In the Roman Republic, it was known as the Year of the Tribunate of Esquilinus, Capitolinus, Vulso, Medullinus, Saccus and Vulscus (or, less frequently, year 354 Ab urbe condita). The denomination 400 BC for this year has been used in Europe since the early medieval period, when the Anno Domini calendar era became prevalent there.

Millennium: 1st millennium BC
400 BC in various calendars
Gregorian calendar400 BC
Ab urbe condita354
Ancient Egypt eraXXVIII dynasty, 5
- PharaohAmyrtaeus, 5
Ancient Greek era95th Olympiad (victor
Assyrian calendar4351
Balinese saka calendarN/A
Bengali calendar−992
Berber calendar551
Buddhist calendar145
Burmese calendar−1037
Byzantine calendar5109–5110
Chinese calendar庚辰年 (Metal Dragon)
2297 or 2237
    — to —
辛巳年 (Metal Snake)
2298 or 2238
Coptic calendar−683 – −682
Discordian calendar767
Ethiopian calendar−407 – −406
Hebrew calendar3361–3362
Hindu calendars
 - Vikram Samvat−343 – −342
 - Shaka SamvatN/A
 - Kali Yuga2701–2702
Holocene calendar9601
Iranian calendar1021 BP – 1020 BP
Islamic calendar1052 BH – 1051 BH
Javanese calendarN/A
Julian calendarN/A
Korean calendar1934
Minguo calendar2311 before ROC
Nanakshahi calendar−1867
Thai solar calendar143–144
Tibetan calendar阳金龙年
(male Iron-Dragon)
−273 or −654 or −1426
    — to —
(female Iron-Snake)
−272 or −653 or −1425
Map of the world in 400 BC.
Celtic influence in Europe 400 BC (blue and purple).


By placeEdit

  • Artaxerxes II, king of Persia, appoints Tissaphernes to take over all the districts in Asia Minor over which Artaxerxes II's brother Cyrus had been governor before his revolt.
  • Xenophon's "Ten Thousand" make their way back to Greece, with most of the men enlisting with the Spartans. Xenophon's successful march through the Persian Empire encourages Sparta to turn on the Persians and begin wars against the Persians in Asia Minor.
  • With the outbreak of the war between Sparta and the Persians, the Athenian admiral, Conon, obtains joint command, with Pharnabazus, of a Persian fleet.
  • War breaks out between Sparta and Elis.
  • London has its origins on a rise above marshy waters at the point where the Walbrook joins the River Thames. The Celtic king, Belin, rebuilds an earth wall surrounding a few dozen huts and orders a small landing place to be cut into the south side of the wall, along the river front, where a wooden quay is built (approximate date)
  • Amyrtaeus of Sais successfully completes a revolt against Persian control by gaining control of all of Upper Egypt.
  • The Olmec culture in Mesoamerica comes to an end as its city of La Venta is abandoned (approximate date).
  • San Lorenzo Tenochtitlán is abandoned (approximate date).

By topicEdit