OK lets start with a bit of a moan. The full title of the book is God's Executioner: Oliver Cromwell and the Conquest of Ireland. So I think it's fairly reasonable to think that the book will be about, well Oliver Cromwell and the period of time that he was in Ireland with a section covering the period prior to Cromwell's direct involvement and another following his return to England to deal with the pesky Scotts. I suppose in fairness this is more or less what you get but I can't shake the idea that Cromwell's name was used more to sell extra copies than his being a central character within the book.
Dr Micheal O' Siochru does a good job of setting the scene and comes across at the start as being able to write up a historical vision without taking up either sides cause. As I got further into the book though I found that he came across as being Partisan to one side then the other almost like he was arguing with himself or really was not sure who was right. This is really the crux of the book though, at times it could be confusing what conclusions the author was coming to but he does make one thing very clear, that neither side could hold there heads up with pride for how they conducted themselves. The Catholics seem to have been doomed to failure due to internal power struggles. a lack of a clear purpose and intervention from Rome that forced the Irish into a no win situation. What made the situation worse was that it was not as simple as two sides, within the Catholic camp you had Old Irish and New Irish (often two generations of what was English Catholics) and Rome, whilst set against these you had English Settlers of the New Prayer Book bent, English troops under command of Ormond (Loyal to Charles I), troops under command of Parliament and troops and settlers that were Scottish. At any one time many of these factions could be working together or against each other and loyalties were more than a little blurred.
Drogheda and Wexford are commonly known as Cromwell's worst cases of excess and you will get few people who will defend his actions here. Though O' Siochru is bold enough to question the level of deaths at Drogheda and I personally think you can run parallels to the Atomic bombs dropped on Japan, the argument that such actions saved other lives as many Towns surrendered before a storming in fear of what would follow, even after Cromwell had left Ireland. The other side of the coin was the killing of Irish by the Irish and burning of Villages within Parliament control by the Catholic forces, especially after the field armies had been defeated and large scale resistance had been replaced by a more Partisan style resistance movement with Catholic forces taking refuge in the peat bogs and sallying out to attack any venerable Parliamentary garrison or body of marching troops. Indeed whilst this would never gain Ireland's freedom from the English Parliament it did more damage than any of the armies that had taken the field.
By the very nature of the conflict it is confusing to follow, but O' Siochru did a fairly good job of helping you understand the events. By the end of the book I could not help but feel sorry for the Catholic people of Ireland, the Gentry come across as self serving, the Church as Manipulative, Rome as just uncaring but the people, well they just suffered no matter who or what happened. As for Ormond, well I already knew of his incompetence but was not aware of how desperately he clung to power for his own sake rather than that of the two Charles. Whilst Cromwell is cast as the villain of the times I can't help but feel he was the most honest of them all. Same for Parliament, yes at times it was underhand but given the double dealings of the rest it came out the better looking of the lot. As such it was a fascinating book that has increased my interest in Ireland during the 17th Century so as such has achieved it's goal.
From a wargaming perspective I have to say that it's a bit of a damp squid. Few large battles occurred and what did were very much one sided so no conversions to Irish regiments required. What could be done though would be skirmish games with 10-30 odd figures per side based on raids, ambushes and rustling. Makes it almost worth buying some 28mm's and giving it a go.