|Centuries:||4th century – 5th century – 6th century|
|Decades:||380s 390s 400s – 410s – 420s 430s 440s|
|Years:||409 410 411 – 412 – 413 414 415|
|412 by topic|
|State leaders – Sovereign states|
|Birth and death categories|
|Births – Deaths|
|Establishment and disestablishment categories|
|Establishments – Disestablishments|
|Ab urbe condita||1165|
|Bahá'í calendar||−1432 – −1431|
|English Regnal year||N/A|
|Chinese calendar||辛亥年 (Metal Pig)
3108 or 3048
— to —
壬子年 (Water Rat)
3109 or 3049
|- Vikram Samvat||468–469|
|- Shaka Samvat||334–335|
|- Kali Yuga||3513–3514|
|Igbo calendar||−588 – −587|
|Iranian calendar||210 BP – 209 BP|
|Islamic calendar||216 BH – 215 BH|
|Minguo calendar||1500 before ROC
|Thai solar calendar||955|
|Wikimedia Commons has media related to 412.|
Year 412 (CDXII) was a leap year starting on Monday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Honorius and Theodosius (or, less frequently, year 1165 Ab urbe condita). The denomination 412 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. 412 is the 412th number in the English number sequence.
- The Visigoths, led by king Ataulf, move into the south of Gaul. He established his residence at Narbonne and makes an alliance with emperor Honorius against the usurper Jovinus.
- Emperor Jovinus elevates his brother Sebastianus as co-emperor (Augustus) and takes control of Gaul.
- Heraclianus, governor (Comes Africae), revolts against Honorius and proclaimed himself Augustus. He interrupts the grain supply to Rome. Honorius condemns him and his supporters to death with an edict at Ravenna.
- The Theodosian Walls are constructed at Constantinople during the reign of emperor Theodosius II. The work is carried out under supervision of Anthemius, notable praetorian prefect of the East.
- Winter – Olympiodorus, historical writer, is sent on an embassy by Honorius and sails in stormy weather around Greece up the Black Sea to meet the Huns who are located on the middle Danube (modern Bulgaria).
- The forts on the west bank of the Danube, which were destroyed by the Huns, are rebuilt, and a new Danubian fleet is launched.
- An edict of Honorius outlaws Donatism.
- Cyril of Alexandria becomes Patriarch of Alexandria.
- Lazarus, bishop of Aix-en-Provence, and Herod, bishop of Arles, are expelled from their sees on a charge of Manichaeism.
- Fa-Hien, Chinese Buddhist monk, spends 2 years in Ceylon and is more than 200 days at sea as storms drive his ship off its course, but returns with sacred Buddhist texts back to China (see 414).
- Lu Huinan, empress dowager of the Liu Song Dynasty (d. 466)
- February 8 – Proclus, Greek Neoplatonist philosopher (d. 485)
- Qifu Gangui, prince of the Xianbei state Western Qin
- Sarus, Gothic chieftain
- October 15 – Theophilus, Patriarch of Alexandria
- Uldin, chieftain of the Huns
- Wang Shen'ai, empress of the Jin Dynasty (born 384)
- The End of Empire (p. 69). Christopher Kelly, 2009. ISBN 978-0-393-33849-2