Athanasius recounts being a student, as well as being educated by the Martyrs of the Great (tenth) and last persecution of Christianity by pagan Rome.[citation needed] This persecution was most severe in the East, particularly in Egypt and Palestine. Peter of Alexandria, the 17th archbishop of Alexandria, was martyred in 311 in the closing days of that persecution, and may have been one of those teachers. His successor as bishop of Alexandria, Alexander of Alexandria (312–328) was an Origenist as well as a documented mentor of Athanasius. According to Sozomen, Bishop Alexander "invited Athanasius to be his commensal and secretary. He had been well educated, and was versed in grammar and rhetoric, and had already, while still a young man, and before reaching the episcopate, given proof to those who dwelt with him of his wisdom and acumen". Athanasius's earliest work, Against the Heathen – On the Incarnation (written before 319), bears traces of Origenist Alexandrian thought (such as repeatedly quoting Plato and used a definition from Aristotle's Organon) but in an orthodox way. Athanasius was also familiar with the theories of various philosophical schools, and in particular with the developments of Neo-Platonism. Ultimately, Athanasius would modify the philosophical thought of the School of Alexandria away from the Origenist principles such as the "entirely allegorical interpretation of the text". Still, in later works, Athanasius quotes Homer more than once (Hist. Ar. 68, Orat. iv. 29). In his letter to Emperor Constantius, he presents a defense of himself bearing unmistakable traces of a study of Demosthenes de Corona.