400s BC

500s BC · 400s BC · 300s BC
Decades of the 400s BC:
490s BC · 480s BC · 470s BC · 460s BC · 450s BC · 440s BC · 430s BC · 420s BC · 410s BC · 409–400 BC

400s BC may refer to:

The period from 499 BC to 400 BC, almost synonymous with the 5th century BC
409–400 BC, rarely

This disambiguation page lists articles associated with the same title.
If an internal link led you here, you may wish to change the link to point directly to the intended article.