This question is not of course about the Flavian Dynasty of Rome (Vespasian, Titus, and Domitian), but rather how a majority of late Roman Emperors took the name Flavius as Emperor.
Examples: Constantine, his sons, Julian, the Valentinian and Theodosian Dynasties, and Justinian.
hi! this question has come up a few times in this sub; you may be interested in answers in previous posts...
Roman Genus/Nomem standards and explaination, with a bit of follow-up here Why do Romans of the late period all seem to bear the name Flavius?
Why is the name Flavius a sign of social status in the Late Roman Empire?
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