The City of God by Saint Augustine

According to the editors preface: The City of God is the masterpiece of the greatest genius among the Latin Fathers, and the best known and most read of his works, except the Confessions. It embodies the results of thirteen years of intellectual labor and study (from A.D. 413-426). It is a vindication of Christianity against the attacks of the heathen in view of the sacking of the city of Rome by the barbarians, at a time when the old Greco-Roman civilization was approaching its downfall, and a new Christian civilization was beginning to rise on its ruins. It is the first attempt at a philosophy of history, under the aspect of two rival cities or communities -- the eternal city of God and the perishing city of the world.