"Lucius Domitius Domitianus was a Roman usurper against Diocletian, who seized power for a short time in Aegyptus.
Domitianus revolted against Diocletian in 297 AD; it is ...
possible that the rebellion was sparked by a new tax edict, but this uncertain. Numismatic and papyrological evidence support Domitianus´ claim to the purple.
Domitianus died in December of the same year, when Diocletian went to Aegyptus to quell with the revolt. Domitianus´ corrector, Aurelius Achilleus, who was responsible for the defense of Alexandria, appears to have succeeded to Domitianus´ claim to the empire; in fact, it was only in March 298 that Diocletian succeeded in re-conquering the city." - (en.wikipedia.org 25.05.2020)