This document summarizes the early history and spread of Christianity from the 2nd to 5th centuries AD. It discusses periods of persecution under Roman emperors like Decius and Diocletian, as well as the martyrdom of figures like Perpetua and Polycarp. It also covers the development of heresies such as Gnosticism, theological debates, and the work of early Church fathers and apologists. Constantine's Edict of Milan ended persecution in 313 and Christianity became the official state religion under Theodosius I in 380. The document traces the spread of Christianity to areas like Armenia, Ethiopia, Italy, France, and England during this time period.