290s

The 290s decade ran from January 1, 290, to December 31, 299.

thumb|right|300px|Map of the late Roman Diocese of Egypt (Late Antiquity)|Diocese of Egypt, with Thebais in the south. The Thebaid or Thebais (, Thēbaïs) was a region in ancient Egypt, comprising the 13 southernmost nomes of Upper Egypt, from Abydos to Aswan.

episode in Roman history, during which a Roman naval commander, Carausius, declared himself emperor over Britain and northern Gaul