Year 411 BC was a year of the pre-Julian Roman calendar.
|Millennium:||1st millennium BC|
|Centuries:||6th century BC – 5th century BC – 4th century BC|
|Decades:||440s BC 430s BC 420s BC – 410s BC – 400s BC 390s BC 380s BC|
|Years:||414 BC 413 BC 412 BC – 411 BC – 410 BC 409 BC 408 BC|
- The democracy of Athens is overthrown. A "Council of Four Hundred" is set up. * Phrynichus, the leader of the extremists, is killed. The traditional constitution is put back.
- The Athenian navy under Thrasybulus calls Alcibiades back from Sardis.