The emperor Constantine changed the world by making the Roman Empire Christian. Eusebius wrote his life and preserved his letters so that his policy would continue. This English translation is the first based on modern critical editions. Its Introduction and Commentary open up the many important issues the Life of Constantine raises.

Averil Cameron is Warden of Keble College, Oxford. The Rev. Stuart Hall is a retired priest in the Scottish Episcopal Church, formerly priest in charge of St John's Pittenweem and St Michael's Elie.