Marcus Aurelius Numerianus was the son of Carus and younger brother of Carinus. In 282 he was proclaimed Caesar. He soon married the daughter of a prefect of the Praetorian guard and along with his father in law, followed his father Carus to battle against the Sassanids.
When his father died in 283 Numerian was proclaimed Augustus and pressured by the army to return to their bases in Europe. On their return it was said that he developed an eye infection in which he needed to travel in a coach to have a better chance of recovery.
According to records the soldiers smelled something terrible a couple of days into their return and found that Numerian had died in the coach. Valerius Diocles accused the father in law Aper of murdering the young emperor and had him killed, Diocles was then named emperor by the troops and adopted the name Diocletian.
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