That said, I'm still excited about this (not least because there are something like 1,000 people involved in the Facebook group at this point!). I was an Ancient History/Classics minor in undergrad, and I am always delighted to be able to get back to that era whether in scholarship or in devotional reading. This project, of course, combines both.
To that end, I thought one of the small ways I might be able to draw on my background and contribute to the discussion (even before it's really begun) is by pointing out some resources that I have found helpful in thinking about the Augustine and the Early church in its Greek and Roman setting.
Not all of these books are for everyone, some require more background knowledge than others, and some are just difficult. So I've broken these books up into levels of difficulty (not length--some of the "beginner" books are quite long, while some of the "advanced" ones are fairly short). And I've kept these mostly historical, rather than theological or philosophical, because that's what I'm more familiar with.
The Christians as the Romans Saw Them by Robert Louis Wilken (reviewed here). This is one of the best books about the ancient world I have ever read. Wilken is a clear and concise writer who knows his sources well and explains the complex ideas and events of the 2nd, 3rd, and 4th centuries with a delightful and engaging style. While Wilken does not carry the narrative through to Augsutine's time, this is essential reading for understanding the pagan views of Christianity that Augustine is arguing against in City of God.
The Early Church by Henry Chadwick. This is the standard introduction to church history and covers the major events in the history of the church from the time of the Apostles through the early 6th century.
How Rome Fell: The Death of a Superpower by Adrian Goldsworthy gives the bare-bones narrative of the collapse of Rome in the 4th and 5th centuries AD. Goldsworthy is a skilled writer and historian and breaks down the complex and obscure events of the collapsing Roman state in a way that even a layman can understand and appreciate.
The Fall of the Roman Empire: The Military Explanation by Arthur Ferrill. If you don't have time to read the lengthy Goldsworthy volume, Arthur Ferrill's The Fall of the Roman Empire is a shorter (and consequently less detailed) overview of the same events. Ferrill just gives the military details of Rome's collapse, and so this book lacks the subtlety and nuance of How Rome Fell, but all the necessary details are there to fill in the background to City of God.
Augustine of Hippo by Henry Chadwick. This is the standard short and simple biography of Augustine that touches on the major issues and details of Augustine's life. Chadwick is a fantastic writer, and this book is the biography to use as an intro to Augustine.
Augustine: A Very Short Introduction by Henry Chadwick. Exactly as the title says, this is a very short introduction to the life and thought of Augustine. Here, Chadwick further distills his biography of Augustine into the bare essentials. And yet for all its brevity, it is not shallow--Chadwick manages in a few pages to give both a detailed view of a psychologically complex man and all the essential facts of his life.
Early Christian Thought and the Classical Tradition by Henry Chadwick. Like the Wilken book above, this book provides a background to the philosophical problems Augustine engages in City of God, rather than an analysis of Augustine himself. Specifically, Chadwick gives a brief overview of the interactions of Tertullian, Justin Martyr, Clement of Alexandria, and Origen with the Greek philosophical tradition--all topics raised by Augustine.
Augustine of Hippo by Peter Brown. Where Chadwick's biography is a good introduction, Brown's classic gives a thorough exploration of Augustine's life and times in the social and political setting of the Ancient World. While not specifically theological, this book really is necessary reading for all serious Augustine students.
Augustine for Armchair Theologians by Stephen Cooper. This is one of the best books in a series of very uneven quality (with the Luther volume being the best, so far anyway). And yet, it's not quite the place to begin reading about Augustine. Cooper assumes a bit more knowledge on the part of the reader than is probably warranted in what is supposed to be an introductory work. For all that, Augustine for Armchair Theologians does provide a good refresher if you've already been exposed to Augustine (much the same could be said of Augustine and his World by Andrew Knowles).
The World of Late Antiquity by Peter Brown gives an alternative to the traditional fall-of-Rome narrative, arguing that instead of a Gibbon-esque "decline and fall" (see below), the Western world underwent a slow transition/evolution into the time we now call the Middle ages. This book is an easy read, but I put it in the "intermediate" category simply because in order to engage Brown's arguments it's useful to have some introductory material under your belt already. Augustine, of course, is a key transitional figure in this evolutionary process.
Pagans and Christians by Robin Lane Fox. If you read only one book by Lane Fox, read his biography of Alexander the Great. But if you read another one, Pagans and Christians is a fascinating exploration of religion in the late Roman Empire. Rather than accepting the standard explanation that paganism was functionally dead by the time Christianity arose, Lane Fox argues that it was vital and vibrant and gave Christianity a real run for its money in the 4th century. From this perspective, City of God is one of the final blows in a battle that had been waging for three hundred years.
The Fall of Rome and the End of Civilization by Bryan Ward-Perkins. This book gives the details of Rome's fall from an archaeological point of view, and so makes the "advanced" category largely because it is such a slog to read. Don't get me wrong, the information here is fascinating, but at the end of the day it's still a book about how the distribution of pottery shards changed between the 4th and 5th centuries. Frankly, that's a topic which you've got to be pretty dedicated to get through. Nevertheless, it makes this list because of the detail it fills in for Augustine's theological narrative.
The End of the Ancient World and the Beginning of the Middle Ages by Ferdinand Lot. This series of lectures is a exploration of the events of the 4th, 5th, and 6th centuries that brought about the end of Rome and the beginning of the Medieval order. Lot deals primarily with economics and politics rather than religion, which makes this work (along with Ward-Perkins) a good supplement to City of God.
Decline and Fall of the Roman Empire by Edward Gibbon. In an ideal world, every Politics and History major would have to read this behemoth in college. But, in a post-fall world, the best we can hope for is that some people will occasionally skim an abridged edition of Gibbon's masterpiece. While there is much here to disagree with, Gibbon's narrative is elegant, elevated, and thorough as he analyzes the events and causes of the fall of Rome. This first three volumes culminate in the destruction of the Western Empire and give extended attention to Augustine from an Enlightenment Secularist perspective. Whether we agree or disagree with Gibbon, we cannot ignore him.
Christianity and Classical Culture by Charles Norris Cochrane. If Wilken, Chadwick, and Brown are the writers to use as a foundation to the study of Augustine (and they are!), then Cochrane is the writer to use as a capstone. Cochrane syenthisizes the history and philosophy of the first five centuries AD beginning with the political thought of Augustus Caesar that attempted to unify the Roman world in an eternal political system and ending with the theology of Augustine's City of God that would explore the collapse of that system in the light of the eternal heavenly city founded in the Gospel and existing in this world by faith. Cochrane is a good writer, but his ideas are dense enough to make this book a significant amount of work to get through. It is, however, work that is immensely rewarding.
And, because there may be one or two of you out there who 1) have lots of spare time on your hands and 2) are borderline clinically insane and want to read more than one ancient document simultaneously, there are at least two primary sources that are interesting to read alongside Augustine:
Jerome: The cranky old translator of the Vulgate saw the same events as Augustine, but came to different conclusions, for if Rome can fall, what can stand? Jerome lacked the theological subtlety of an Augustine, but he more than made up for it in personality, assertiveness, and linguistic brilliance.
Salvian: This obscure writer was a younger contemporary of Augustine who lived in the south of France with a front-row view of the barbarian invasions and the steady destruction of the Western Roman Empire. Salvian, perhaps because of his location, comes to some much less optimistic conclusions about the disaster currently overwhelming Rome than the cheerful-by-comparison Augustine.
There are also quite a few books that I've heard good things about, but haven't read myself. So without further comment:
Augustine: A New Biography by James O'Donnell
The Ruin of the Roman Empire: A New History by James O'Donnell
Saint Augustine: A Life by Gary Willis
The Fall of the Roman Empire: A New History of Rome and the Barbarians by Peter Heather
Empires and Barbarians by Peter Heather
The Fall of the Roman Empire by Michael Grant
Studies in Tertullian and Augustine by B.B. Warfield (I know, I know, I said mostly history, but this really is a worthwhile study of Augustine at least--the Tertullian essays are pretty dull. It's in the supplement section because I've read it, but it's not fundamentally historical in nature.)
And just for fun:
by B.B. Warfield
(not included in the volume listed above, which is fine since it's not a great poem)
"There is a place for everything,
In earth or sky or sea,
Where it may find its proper use
And of advantage be,"
Quoth Augustine, the saint.
The mocker quick with curling lip:
"Then there's a place for vice
Yea fitly 'neath our trampling feet
May lie the cockatrice,"
Quoth Augustine, the saint.
"Our very vices great and foul,
When in the earth they're trod
May haply lofty ladders build
On which to climb to God,:
Quoth Augustine, the saint.