Preventive law in early Ireland. Rereading the Additamenta in the Book of Armagh

This article argues that the so-called Additamenta, found on ff. 16r–18v of the Book of Armagh, may have functioned as a form of preventive law. Reading the Additamenta in this fashion suggests that the evidence they adduce to legitimize Armagh's property rights reflects those categories of claims thought most likely to prevail should the foundation's landholdings fall into dispute. As an archive of documents that both preserved and shaped institutional memory, they provided a historical frame that limited the possibility of challenges to Armagh's standing or, if those challenges did come to trial, shaped the court's perception to the foundation's benefit. Consequently, even if these documents do not necessarily reflect an ongoing charter tradition, we may still use them as case studies revealing one way in which early Irish landowners—especially those associated with ecclesiastical foundations like Armagh—utilized text and narrative to influence the progress of legal disputes.