The Celestial Hierarchy is part of a late-fifthcenturyor early-sixth-century body of Greek literature that would later become known (in Latin) as the Corpus Areopagiticum, that is, the body of writings from (Dionysius) the Areopagite. These texts, likely composed in the area around Syria, reflect elements of Neoplatonic philosophy, controversial issues of Christian theology, along with components of mysticism. The Corpus survives in the form of four treatises (The Celestial Hierarchy, The Ecclesiastical Hierarchy, The Divine Names, and The Mystical Theology) along with ten letters supposedly written in the first century by Dionysius the Areopagite. The actual authorship is a problem of some complexity, and the author has long been known as Pseudo-Dionysius.