Monastic Formation
Born Alexius (also recorded as Athanasius's baptismal name in some accounts) in Adrianople, the future patriarch left home in his youth and traveled to Thessalonica, where he was tonsured in one of its monasteries and given the name Acacius. Tradition holds that he was orphaned young and was drawn to the monastic path by reading of the life of an earlier ascetic.
He subsequently relocated to Mount Athos, where he joined the community of Esphigmenou Monastery and served in the refectory for three years while deepening his ascetic discipline. Seeking greater solitude, he moved on through several communities — including the Auxention monastery and, by tradition, hermitages on Mount Ganos in Thrace and elsewhere — before settling at the monastery of Blessed Lazarus on Mount Galanteia. There he accepted the great angelic schema with the name Athanasius, was ordained a priest, and served as ecclesiarch.
Patriarchate and Reform
Athanasius was chosen as Patriarch of Constantinople by Emperor Andronikos II Palaiologos, and served a first term from 14 October 1289 to 16 October 1293. He opposed the reunion of the Greek and Roman Churches — he was aligned with the anti-union party that had formed after the Second Council of Lyon in 1274 — and introduced an ecclesiastical reform program that provoked opposition within the clergy, leading to his resignation in 1293.
Backed by popular support, he was restored to the patriarchal throne on 23 June 1303, serving a second, contentious term until September 1309. During this period, in 1308, he established Saint Peter as Metropolitan of Kiev and All Rus. The pro-union clerical faction ultimately forced him into retirement. His reforms and social policies, together with his correspondence with imperial officials, have been the subject of substantial academic study, notably by John L. Boojamra and Alice-Mary Talbot.
Relics & Shrines
A set of relics long believed to belong to Saint Athanasius the Great of Alexandria was later identified as belonging instead to Athanasius I of Constantinople. These relics were brought to Venice in 1455 and housed in the Church of San Zaccaria, where they were for a long time mislabeled as those of the more famous Alexandrian patriarch.
Traditional Accounts
By tradition, while serving as ecclesiarch at the monastery of Blessed Lazarus, Athanasius received a divine calling toward ecclesiastical leadership through a voice from a crucifix. Near the end of his life, the synaxarion relates, he received a vision of Christ, was granted forgiveness for his early resignation from office, and was given the gift of wonderworking. He is said to have died at approximately one hundred years of age.
