Our father among the saints Alexander of Alexandria was the Pope of Alexandria and leader of the Church of Alexandria during the early part of the fourth century. During his reign he had to deal with major issues that confronted the Church as it gained its freedom from Roman persecutions, including the rise of Arianism and the dating of Pascha. He was a leader of the opposition to the heresy of Arianism at the First Ecumenical Council. He is remembered on May 29.