Maximian - Appointment As Caesar

Appointment As Caesar

At Mediolanum (Milan, Italy) in July 285, Diocletian proclaimed Maximian as his co-ruler, or Caesar. The reasons for this decision are complex. With conflict in every province of the Empire, from Gaul to Syria, from Egypt to the lower Danube, Diocletian needed a lieutenant to manage his heavy workload. Historian Stephen Williams suggests that Diocletian considered himself a mediocre general and needed a man like Maximian to do most of his fighting.

Next, Diocletian was vulnerable in that he had no sons, just a daughter, Valeria, who could never succeed him. He was forced therefore to seek a co-ruler from outside his family and that co-ruler had to be someone he trusted. (The historian William Seston has argued that Diocletian, like heirless emperors before him, adopted Maximian as his filius Augusti ("Augustan son") upon his appointment to the office. Some agree, but the historian Frank Kolb has stated that arguments for the adoption are based on misreadings of the papyrological evidence. Maximian did take Diocletian's nomen (family name) Valerius, however.)

Finally, Diocletian knew that single rule was dangerous and that precedent existed for dual rulership. Despite their military prowess, both sole-emperors Aurelian and Probus had been easily removed from power. In contrast, just a few years earlier, the emperor Carus and his sons had ruled jointly, albeit not for long. Even the first emperor, Augustus, (r. 27 BC–AD 19), had shared power with his colleagues and more formal offices of co-emperor had existed from Marcus Aurelius (r. 161–180) on.

The dual system evidently worked well. About 287, the two rulers' relationship was re-defined in religious terms, with Diocletian assuming the title Iovius and Maximian Herculius. The titles were pregnant with symbolism: Diocletian-Jove had the dominant role of planning and commanding; Maximian-Hercules the heroic role of completing assigned tasks. Yet despite the symbolism, the emperors were not "gods" in the Imperial cult (although they may have been hailed as such in Imperial panegyrics). Instead, they were the gods' instruments, imposing the gods' will on earth. Once the rituals were over, Maximian assumed control of the government of the West and was dispatched to Gaul to fight the rebels known as Bagaudae while Diocletian returned to the East.