I am afraid this book was a disappointment. For me ,alternative ("Counter-factual") history only really works if the genuine historical characters introduced in the piece speak, act and react as they would have done if the twist in circumstances that prompted the writing of the book in the first place had actually occured. But in the very first chapter there is a quite preposterous conversation between Palmerston, Russell and Gladstone which,for me, under-mined the plot from the first.Mr Conroy really should research his historical characters more before putting words into their mouths.The book is also riddled with irritating historical inaccuracies and probable misconceptions which further fractures the illusion of truth e.g.Lord Lyons was not "Ambassador Lyons" at the time: given the composition of the British Army throughout the 19th.Century it is most unlikely that an Irishman would be condemned because he "spoke funny": Sir Garnet's name was not spelt "Wolsey" etc etc.
It could have been done so much better.