Marcus Claudius Tacitus may have been an old man, but he still had a lot of energy left. He immediately punished some of the soldiers involved in the death of his predecessor Aurelianus. Mucapor was tortured to death, but some of the conspirators apparently managed to get away, for they were later punished by Tacitus’ successor Probus (see below). The notoriously unreliable Historia Augusta claims the emperor instituted a ban on brothels in Rome, but had to reverse that decision just a little later because the ban could not be enforced. Tacitus was also said to have promoted the work of the historian Tacitus, a man he claimed descent from. Even if the emperor did make this claim, there is no reason to assume the historian and the emperor were related: their family names – Cornelius vs. Claudius – are completely different. The latter may simply have been an admirer of the former, and the fact that they shared the same cognomen (‘Silent’) was likely just a coincidence. Having – or claiming to have – an illustrious ancestor was of course also a useful political tool.
Campaigns, death and succession
Tacitus and his praetorian prefect, Marcus Annius Florianus, had little time to spent in the capital. In early 276 they left for Asia Minor where the Goths had invaded. These had first raided Pontus and then advanced all the way into Cilicia. The emperor and his prefect managed to catch up with them and destroy their forces. Some of Tacitus’ coins have the text VICTORIA GOTTHI and in inscriptions we find the agnomen ‘Gothicus Maximus’. Not long afterwards, probably in June, Tacitus died in Tyana, Cappadocia, and the Empire was faced with another succession crisis.
The sources give us conflicting accounts of the circumstances of the emperor’s death. The anonymous author of the Epitome de Caesaribus states that he died of a fever, while Aurelius Victor and Zosimus claim that he was murdered. In Zosimus’ version, the emperor had appointed his cousin Maximinus governor of Syria, who quickly became hated because of his strictness. The local nobles began conspiring against him and sent out assassins to kill him. These men were reportedly the surviving murderers of Aurelianus. Whoever they were, the men were successful in their mission. Maximinus was killed, but so was Tacitus. The Historia Augusta mentions both versions: murder and death of disease. But whichever version is correct, the result was the same: the emperor was dead after little more than six months on the throne.
Florianus now proclaimed himself emperor. He may have been the late emperor’s half-brother, although that familial relation may have been a fabrication to give his claim to the throne more legitimacy. Although the Senate seems to have accepted him as the new Augustus and Tacitus’ army certainly did, one Marcus Aurelius Probus did not. He was another Illyrian officer, who like the emperors Decius and Aurelianus had been born in or near Sirmium in Pannonia (modern Sremska Mitrovica in Serbia). Probus was serving as governor of a couple of eastern provinces at the time, including Syria and Egypt, so he may have been appointed as the aforementioned Maximinus’ successor. Hearing of the emergence of a rival, Florianus let the surviving Goths escape and advanced on Tarsus in Cilicia, where the two armies camped opposite each other.
In the end there was not much fighting. Zosimus claims that disease broke out in Florianus’ camp and that his European soldiers were not used to the Cilician heat. They ultimately weighed their options, switched sides and murdered Florianus, probably in September. Probus – the name means ‘Honest’ – was now the sole Augustus. He was another barracks emperor, a true soldier who spent most of his reign on campaign. The new emperor had the surviving assassins of Aurelianus executed, as well as those who slew Tacitus (if indeed the man was murdered). His throne now being secure, he left Asia and travelled to Gaul to fight off invasions by the Franks and Alemanni.
- Aurelius Victor, De Caesaribus 36 (translated and annotated by H.W. Bird);
- Epitome de Caesaribus 36;
- Historia Augusta, The Life of Tacitus;
- Zosimus, Historia Nova, Book 1.63-65.
- Adrian Goldsworthy, The Fall of the West, p. 132-133.
 CIL 17-02, 00174.