Ante-Nicene Church
- Writings of the "Apostolic Fathers" (Didache, Papias, Epistle of Barnabas, 2 Clement) (100–160)
- Justin Martyr – apologist and teacher of the Logos (early 2nd c. – 165)
- Gnosticism as the chief threat to the Church in the 2nd century (1st–2nd c.)
- Early Christian worship, baptism, and church order (2nd–3rd c.)
- The spread of Christianity across and beyond the empire (100–312) (100–312)
- Why Rome persecuted Christians: the causes of the persecutions (1st–3rd centuries) (1st–3rd centuries)
- The martyrdom of Ignatius of Antioch and his letters (107 or 115)
- The correspondence of Pliny the Younger with Trajan concerning the Christians (111–117)
- Second-century apologists (Aristides, Tatian, Athenagoras, Theophilus of Antioch, Melito of Sardis) (120–200)
- Irenaeus of Lyons and his work Against Heresies (c. 130 – 202 (chief work written c. 180))
- Montanism (the "New Prophecy", the "Phrygian heresy") (mid-2nd c. – early 3rd c.)
- Marcion and the founding of the Marcionite church (139–144)
- The formation of the New Testament canon, the rule of faith, and baptismal creeds (150–200)
- The martyrdom of Polycarp of Smyrna (155 or 156)
- The Quartodeciman Easter controversy (c. 155 – 190s)
- Tertullian of Carthage – founder of Latin theology (160–220)
- Persecution under Marcus Aurelius; the martyrs of Lyon and Vienne (161–180 (Lyon and Vienne – 177))
- Clement of Alexandria and the Alexandrian school of theology (late 2nd c. – 215/216)
- Monarchianism: dynamic and modalist (Noetus, Sabellius, Paul of Samosata) (late 2nd c. – 272)
- Origen of Alexandria: school, On First Principles, the Hexapla, Against Celsus (c. 185 – 254)
- Hippolytus of Rome and the schism against bishop Callistus (c. 200 – 238)
- The persecution of Septimius Severus (202)
- Mani and the rise of Manichaeism (216–277 (preaching 242–247))
- Cyprian of Carthage and the controversy over the "lapsed" (248/249 – 252)
- The persecution of Emperor Decius (249–251)
- The first desert monks: Paul of Thebes and Antony the Great (mid-3rd c. – 356)
- Genealogies of Christian Mystical Theology: from Origen to the Quietist Controversy (3rd–17th centuries)
- The Novatianist schism at Rome (251)
- The rebaptism controversy (Cyprian and Stephen of Rome) (254–258)
- The persecution of Valerian and the martyrdom of Cyprian (257–260)
- Diocletian's reforms and the establishment of the Tetrarchy (284–305)
- The Rise of Egyptian Monasticism: Desert Hermits and Pachomius's Cenobitic Monasteries (4th century)
- The Baptism of Armenia: the Conversion of King Tiridates III (301–303)
- The Great Persecution of Diocletian and Galerius (303–311)
- The Abdication of Diocletian and Constantine's Proclamation at York (305–306)
- The Donatist Schism in North Africa (305–412)
- The Edict of Galerius on Toleration (April 30, 311)
- The Battle of the Milvian Bridge and Constantine's Vision (October 28, 312)