MAP 7.1 Diocletian’s Reorganization of 293

Trying to prevent civil war, Emperor Diocletian reorganized Rome’s imperial territory into a tetrarchy, to be ruled by himself, his co-emperor Maximian, and assistant emperors Constantius and Galerius, each the head of a large district. He subdivided the preexisting provinces into smaller units and grouped them into fourteen dioceses, each overseen by a regional administrator. The four districts as shown here reflect the arrangement recorded by the imperial official Sextus Aurelius Victor in about 360. What were the advantages and disadvantages of subdividing the empire?