A New History of Ireland, Volume I marks the culmination of the largest scholarly project in modern Irish history. It consists of nine volumes, by over a hundred contributors, mainly historians but including also historical geographers and specialists in other disciplines, such as language and literature, the visual arts, and music. Seven of the volumes are text, and deal not only with politics but also with economic, social, and cultural history. The other volumes contain maps and reference material.

As the final volume to appear in this multi-volume series, A New History of Ireland Volume I brings to a close the project initiated by T. W. Moody and R. Dudley-Edwards in the 1960s, to provide a comprehensive new synthesis of modern scholarship on every aspect of Irish history and prehistory, from the earliest geological and archaeological evidence, through the Middle Ages, and down to the present day.

Volume I begins by looking at geography and the physical environment. Chapters follow which examine pre-3000, neolithic, bronze-age and iron-age Ireland and Ireland up to 800. Society, laws, church and politics are all analysed separately as are architecture, literature, manuscripts, language, coins and music. The volume is brought up to 1166 with chapters, amongst others, on the Vikings, Ireland and its neighbours, and opposition to the High-Kings. A final chapter moves further on in time, examining Latin learning and literature in Ireland to 1500.