Dionysius the Great was the 14th Pope and Patriarch of Alexandria from 28 December 248 until his death on 22 March 264. Most information known about him comes from a large corpus of correspondence. Only one complete letter survives; the remaining letters are excerpted in the works of Eusebius.

Basil of Caesarea, also called Saint Basil the Great, was a bishop of Caesarea Mazaca in Cappadocia, Asia Minor. He was an influential theologian who supported the Nicene Creed and opposed the heresies of the early Christian church, fighting against both Arianism and the followers of Apollinaris of Laodicea.