Dionysius, presbyter of Alexandria, succeeded Heraklas as bishop about 247, shortly before the elevation of Cyprian. He was a cultivated man of good education, and in the retrospect of the fourth century was much admired and respected as 'the great'. Within a few months of his consecration his people were the target of mob violence, perhaps especially because the city was beset by plague and civil war, and from early in 250 Decius launched persecution.
At Alexandria bishop Dionysius was target of attacks essentially similar to those suffered by Cyprian. Responsible for a number of people in his house, he decided to take flight when persecution came, was captured after a few days and arrested by soldiers, but then liberated by an onslaught from revellers at a wedding party outraged by their bishop's capture; they forced the guards to run for their lives. Dionysius' letters, cited by Eusebius of Caesarea, record the horrors endured by elderly Christians during the pogrom of 249 and then, in 250 under Decius, the sad lapse of many, and their ferocious treatment by the Alexandrian mob. He found it necessary to defend himself against sharp criticism from another Egyptian bishop Germanos who directly accused him of cowardice: ought he not to have stayed at his post and shared martyrdom with the confessors of his flock?
In his Preparation of the Gospel (book 14) Eusebius preserves substantial pieces of Dionysius' treatise 'On Nature', defending design in the cosmos against the random chance of Epicureanism. The context is likely to have been a widespread loss of inward security and confidence in providence resulting from the chaotic state of the Roman empire in the mid-third century. Dionysius was clear that even during terrible times divine care had not ceased to operate.
The political disasters of the age could easily have fostered millennialism. The interpretation of the Apocalypse of John of Patmos was no easy matter, but chapter 21 if taken literally (as had been done by Justin and Irenaeus) offered a strong lead for belief in a thousand-year reign of Christ at a rebuilt Jerusalem. Origen, on the other hand, who deeply influenced Dionysius by his biblical exegesis, had been clear that John was writing symbolically and allegorically.
Before Dionysius' time a bishop Nepos of Arsinoe, south of Memphis, had exercised profound influence in Egypt by his spiritual qualities both in bible