400s

Millennium:	1st millennium
Centuries:	4th century – 5th century – 6th century
Decades:	370s 380s 390s – 400s – 410s 420s 430s
Years:	400 401 402 403 404 405 406 407 408 409
Categories:	Births – Deaths – Architecture Establishments – Disestablishments

The 400s was a decade that started on 1 January 400 and ended on 31 December 409.

Events

• Constantine III seizes control of the Roman garrison in Britain, declares himself emperor, and crosses into Gaul.
• August 22, 408 – Stilicho, military power behind the imperial throne, is executed. The Roman military is leaderless for several years until Constantius III becomes patrician.
• Construction (and therefore occupation) at Great Zimbabwe begins.
• Validity limit for the information on Eastern Roman Empire in the Notitia Dignitatum.