540
| Years: 536 537 538 539 - 540 - 541 542 543 544 | |
| Decades: 510s 520s 530s - 540s - 550s 560s 570s | |
| Centuries: 5th century - 6th century - 7th century | |
Events
- Byzantine general Belisarius conquers Milan and the Ostrogoth capital Ravenna.
- Ostrogoth king Witiges is succeeded by Ildibad.
- Pope Vigilius in letters to emperor Justinian and patriarch Patriarch Menas of Constantinople rejects Monophysitism.
- The Sassanids attack Dara and capture Antioch.
- Pope Gregory I (approximate date)
- Galswintha, wife of Chilperic I of Neustria
- Dionysius Exiguus (approximate date)
- Witiges, king of the Ostrogoths