Diocletian are a death/black metal band from Auckland, New Zealand. The band is named after Roman Emperor, Diocletian, who is known for the Diocletianic Persecution (or Great Persecution, 303-311),l which was the last and most severe persecution of Christians in the Roman empire.

Formed in 2004 in the vein of other "war" metal bands like Blasphemy, Conqueror, and Revenge, Diocletian have made a name for themselves in New Zealand and abroad.  Their sound is characterized as a violent black/death metal hybrid that is fast, raw, and chaotic, almost bordering on grind.  Diocletian will be bringing their unique blend of death and black metal to California Deathfest in 2017.