The Irish War of Independence was a sporadic guerrilla campaign that lasted from January 1919 until July 1921. Michael Hopkinson makes full use of the recently opened files of the Bureau of Military Archives in Dublin, which contain valuable first-hand contemporary accounts of the war, meticulously piecing together the many disperate local actions to create a coherent narrative. He stresses the importance of local and contingent issues over the idea of a master plan developed by the Dublin-based republican leadership.

The war was prosecuted ruthlessly by the Irish Republican Army which, paralleling the political efforts of Sinn Féin, hoped to break Britain's will to rule Ireland and create an independent Irish republic. The British retaliated by introducing two new irregular forces into Ireland, the Black and Tans and the Auxiliaries. Fighting took place principally in counties Cork, Limerick, Tipperary, Monaghan, Armagh, Clare, Kerry, and Longford. It was sporadic but vicious, with fewer than 2,000 IRA volunteers facing over 50,000 crown forces. The IRA depended upon energetic local leaders -- where there were none, there was little fighting.