In spite of Ireland’s rich and complex religious history, the influence of the Old Testament in the shaping of the island is often overlooked. This study traces the use and reception of the Old Testament in Ireland through the centuries, focusing on stories of transmission, translation, and unexpected influence. In early Christian and medieval Ireland, the transmission of the Old Testament in diverse contexts points to an important role for the Old Testament in relation to social formation and notions of Irish history. Moving to early modern Ireland, the story of the translation of the Old Testament into Irish demonstrates how this collection contributed to contested issues of identity in this highly-charged era. Finally, we encounter stories of unexpected influence relating to Ireland and the Old Testament in James Ussher and John Nelson Darby. In both cases, ideas concerning the Old Testament that took shape in Ireland would go on to have impact on a global scale, even if this subsequent influence was a matter of accidence. Taken together, it is argued that the Old Testament has played a much more prominent role in the shaping of the social, cultural, and religious landscape of Ireland than is often assumed.