diocletian

noun

1. Gaius Aurelius Valerius Diocletianus, a.d. 245–316, Illyrian soldier: emperor of Rome 284–305.

noun

1. full name Gaius Aurelius Valerius Diocletianus. 245–313 ad, Roman emperor (284–305), who divided the empire into four administrative units (293) and instigated the last severe persecution of the Christians (303)