Liam O'Callaghan's revelatory Blood and Thunder shows that the rise of Irish rugby is inextricable from the tensions, debates and divisions – of politics, religion and class – that have defined modern Irish history.

Despite the political partition of the island, Ireland competes at rugby internationally with an all-island team – and with a bespoke anthem that nobody loves but everyone tolerates. Ireland has become a leading rugby nation despite its tiny population and the fact that the sport is only the fourth most popular team game on the island by participation.

In Blood and Thunder, O’ Callaghan traces the dramatic evolution whereby a rugby nation that was deeply attached to amateurism has made such a dramatic success of professionalism. From the sequence of events that led Ireland's private Catholic secondary schools to embrace rugby, to the controversies and crises that have shaken Irish rugby – including the Northern Troubles, the Belfast rape trial, and the rising toll of head injuries – Blood and Thunder tells the rich and fascinating story of Irish rugby.

Blood and Thunder is more than a social and political history of Irish rugby. It is also a shadow-history of modern Ireland, rooted in brilliant original research and packed with terrific stories.