Diocletian found a solution to the age-old problem of succession: the tetrarchy. Diocletian understood that a major problem in ruling a territory of the extent of the Roman Empire was its immense size. It was far too large to be ruled by just one person, so one of the first actions taken by the new emperor was to split the empire into two parts.

Diocletian thought that is almost impossible to rule the empire because of its huge size. He decided that it was too large to be ruled by one person, and eventually, he split the empire into two parts.

If one is to believe Lactantius, Diocletian divided the provinces “so as to make himself more feared,” but in fact it was to bring the governors closer to those they administered and, by fragmenting their power, to diminish their territorial strength.

In dividing power, Diocletian’s aim was to avoid usurpations, or at least to stifle them quickly—as in the attempt of Carausius, chief of the army of Britain, who was killed (293), as was his successor, Allectus (296), after a landing by Constantius.