On his way back to the west to deal with a Frankish and Alamannic invasion of Gaul, according to Aurelius Victor, Eutropius, and the Historia Augusta, Tacitus died of fever at Tyana in Cappadocia in June 276.
Florian led his troops to Cilicia and billeted his forces in Tarsus. However many of his troops, who were unaccustomed to the hot climate of the area, fell ill due to a summer heatwave. Upon learning of this, Probus launched raids around the city, in order to weaken the morale of Florian's forces. This strategy was successful, and Florian lost control of his army, which in September rose up against him and killed him. In total, Florian's reign lasted less than three months.
Florian, the half-brother of Tacitus, also proclaimed himself emperor, and took control of Tacitus' army in Asia Minor, but was killed by his own soldiers after an indecisive campaign against Probus in the mountains of Cilicia. In contrast to Florian, who ignored the wishes of the senate, Probus referred his claim to Rome in a respectful dispatch. The senate enthusiastically ratified his pretensions.