Diocletian (240–316) was the Roman emperor who instituted the last great persecution against Christians.
The emperor himself, though not yet attached to the Christian religion, has entrusted the care of his life and person to these same Christians as his more faithful servants. Theonas of Alexandria (c. 300, E), 6.158
When Diocletian—that author of ill and deviser of misery—was ruining all things, he could not withhold his insults, not even against God. This man . . . overturned the Roman empire. For he selected three persons to share the government with him. The empire was sectioned into quarters, and so armies were multiplied. Each of the four rulers strove to maintain a greater military force than any single emperor had done in times past. Eventually, there were less men who paid taxes than there were who received wages. As a result, the estate of the farmer was exhausted by enormous taxes. Farms were abandoned; cultivated grounds became woodlands. Universal dismay prevailed. Lactantius (c. 320, W), 7.303