Year 21 was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar.

Events

By place

Roman Empire

• Revolt of the Aedui under Julius Florus and Julius Sacrovir, suppressed by Gaius Silius.
• Tiberius is a Roman Consul for the fourth time.
• Beginning of the revolt in Africa led by Tacfarinas.
• The Romans create a buffer state in the territory of the Quadi in southern Slovakia.
• A barracks is constructed for the Praetorian Guard on the Quirinal.

Asia

• King Daeso of Dongbuyeo is killed in battle against the armies of Goguryeo, led by its third ruler, King Daemusin.

By topic

Arts and Sciences

• Manufacture of pens and metal writing tools in Rome.

Births

Deaths

• Publius Sulpicius Quirinius, Roman governor of Syria
• Marcus Valerius Messalla Barbatus, Roman Consul (or 20)
• Arminius, Germanic leader who killed three Roman legions at the Battle of the Teutoburg Forest
• Empress Wang