Athanasius of AlexandriaAthanasius I of Alexandria (296–298 – 2 May 373), also called Athanasius the Great, Athanasius the Confessor, or, among Coptic Christians, Athanasius the Apostolic, was a church father and the 20th pope of Alexandria (as Athanasius I). His intermittent episcopacy spanned 45 years (8 June 328 – 2 May 373), of which over 17 encompassed five exiles, when he was replaced on the order of four different Roman emperors. Athanasius was a Christian theologian, a Church Father, the chief defender of Trinitarianism against Arianism, and a noted Egyptian Christian leader of the fourth century.
Roman emperorThe Roman emperor was the ruler and monarchial head of state of the Roman Empire during the imperial period, starting with the granting of the title augustus to Octavian in 27 BC. The emperors used a variety of different titles throughout history. Often when a given Roman is described as becoming emperor in English, it reflects his taking of the title augustus and later basileus. Another title often used was caesar, used for heirs-apparent, and imperator, originally a military honorific.
ArianismArianism (Ἀρειανισμός, Areianismós) is a Christological doctrine first attributed to Arius (AD 256–336), a Christian presbyter from Alexandria, Egypt. Arian theology holds that Jesus Christ is the Son of God, who was begotten by God the Father with the difference that the Son of God did not always exist but was begotten/made before "time" by God the Father; therefore, Jesus was not coeternal with God the Father, but nonetheless Jesus began to exist outside time as time applies only to the creations of God.