449
| Years: 445 446 447 448 - 449 - 450 451 452 453 | |
| Decades: 410s 420s 430s - 440s - 450s 460s 470s | |
| Centuries: 4th century - 5th century - 6th century | |
Events
- August 3 - The Second Council of Ephesus opens, chaired by Dioscorus, Patriarch of Alexandria. Flavian, Patriarch of Constantinople, and Domnus II, Patriarch of Antioch, are deposed on August 8.
- October, a Roman synod repudiates all the decisions of the Second Council of Ephesus.
- Anatolius becomes Patriarch of Constantinople
- Maximus II becomes Patriarch of Antioch.
- Vortigern forms an alliance with Hengest and Horsa, by tradition chieftains of the Jutes, who led the Anglo-Saxon invasion of Britain. (traditional date)