I knew a rough outline of modern Irish history before reading this but O'Toole brings it vividly to life in this engaging and informative book. I'd mainly read his work on Britain before, so it was fascinating to see his take in his own country. He explores the decisions made in his youth about what the future of Ireland should be and how they had unintended and unexpected consequences in the decades that followed.
His overall theme of what people knew and chose not to know (the "unknown known") captures the ambiguities of this history and the accumulation of hypocrises that had to be accepted and then forgotten about to prosper.
As ever O'Toole writes in engaging prose with a fantastic ability to turn a phrase that explains the situation and reveals his personal view.