Unfortunately, this is a classic example of a book with a snappy title that fails to live up to it. It is pure style over substance. Cahill is an author with an ax to grind and he is perfectly willing to cherry-pick historical anecdotes to support his thesis while ignoring those that weaken it. His style of scholarship is that annoying modern tendency to ascribe great importance to vague and contradictory statements from the ancients, while questioning and dismissing solid facts that have been commonly held for centuries.
My biggest problem with this book is simply that it takes forever for Cahill to get to "how the Irish saved civilization" and when he finally does get there, his treatment of the Irish contribution to preserving ancient scholarship is completely cursory. I was expecting chapters on Skellig Michael, Iona, Armagh and other centers of Irish monasticism. Instead, we are treated to Cahill's utterly false division of Irish Christianity from Roman Catholicism. He creates a scenario in which Saint Patrick and Saint Augustine are at opposite poles. He condemns Augustine as an "evil cleric" and the son of a domineering mother (Saint Monica) who is full of hatred and contempt for those who dared oppose him. He continually takes pot-shots at traditional Catholic practices, particularly (gasp!) the celibate male priesthood.
Meanwhile, he claims that Irish Christianity is not concerned with such petty matters as sexual purity. He notes that in all his writing, St. Patrick never came anywhere near the subject of sex except to make note of a "beautiful Irish princess." Based on that, he extrapolates that Saint Patrick--and by extension, Irish Christianity in general--was not beholden to the "rigid rules of chastity" enjoined by the Roman Church. His evidence supporting this contention is gossamer thin and almost entirely unreferenced in the book.
Cahill also hints that the Irish Christians tolerated abortion and had women bishops. In case his central theme isn't crystal clear by now, he even writes: "How different might Catholicism be today if it had been taken over by the easy Irish sympathy between churchmen and laymen and the easy Irish attitude toward diversity, authority, the role of women, and the relative unimportance of sexual mores." The answer to this question is that the Catholic Church would have become what mainline Protestant churches are today--dying, enervated museum pieces that accept everything and stand for nothing.
In the end, Cahill can't even bring himself to say that the Irish saving civilization was a good thing. He writes:
Latin literature would almost surely have been lost without the Irish, and illiterate Europe would hardly have developed its great national literatures without the example of the Irish...Beyond that, there would have perished in the west not only literacy but all the habits of mind that encourage thought. And when Islam began its medieval expansion, it would have encountered scant resistance to its plans--just scattered tribes of animists, ready for a new identity. Whether this state of affairs would have been better or worse than what did happen I leave to the reader to ponder.In sum, I would not recommend this book. It is little more than a meandering anti-Catholic polemic dressed up as a tribute to the Irish. A good antidote to this book is How the Catholic Church Built Western Civilization by Tom Woods.