21

Year 21 was a (link will display the full calendar) of the.

Roman Empire

 * Revolt of the under  and Julius Sacrovir, suppressed by.
 * is a for the fourth time.
 * Beginning of the revolt in led by.
 * The Romans create a buffer state in the territory of the in southern.
 * A barracks is constructed for the on the.

Asia

 * is killed in battle against the armies of Goguryeo, led by its third ruler,.

Arts and Sciences

 * Manufacture of s and metal writing tools in Rome.

Deaths

 * Publius Sulpicius, Roman governor of
 * , (or )
 * , Germanic leader who killed three Roman legions at the