According to the Historia Augusta, Firmus (died 273) was a usurper of Syrian origin during the reign of Aurelian.
[1] The contradictory accounts of his life and the man himself are considered to be a complete fabrication, perhaps based on the later Firmus.
He had two elephant tusks, which later Aurelian projected to use as a basis for a statue to Jupiter and which were actually given as a present by Carinus.
The Historia Augusta states that he once consumed an entire ostrich in one day, and even beat one of Aurelian's standard bearers and notorious drinkers in a drinking contest, draining two buckets of wine while remaining completely sober.
The importance and threat of Firmus' revolt is related to the interruption of the Egyptian grain supply to Rome.