States and territories established in the 290s

The Tetrarchy was the system instituted by Roman emperor Diocletian to govern the ancient Roman Empire by dividing it between two emperors, the augusti, and their junior colleagues and designated successors, the caesares. It was kept in place between AD 293 and 324.

Roman province

province of the Roman Empire

Roman province (295 - 5th century)

Roman province (296 - mid-5th century)

Roman province (296 - mid-5th century)

Roman diocese