The Bellews of Barmeath in County Louth number amongst the few landed Catholic families who successfully navigated the penal era in Ireland during the long eighteenth century. They also retain a remarkable family archive at Barmeath Castle. This archive provides the basis for this study of how the penal laws impacted them and how they successfully navigated the challenges. The thesis examines the evolving use of strict settlement by Irish landed families in the seventeenth century and builds on this foundation to examine the impact of the 1704 and 1709 Popery Acts on that usage. In doing so, it provides a much clearer understanding of the actual legal impact of the Popery Acts on Catholic families in their use of strict settlement. The study provides much detail of the Bellews’ experience in navigating the many challenges, including the threat of Protestant discovery and a rare case of a younger son who forced his claim to gavelkind. It also shows how they leveraged the various tools available to Catholics, such as convert lawyers, collusive discovery and Protestant trustees. The focus switches after 1760 to explore the Bellews’ involvement in the political campaigns for Catholic relief and emancipation. By exploring the perspective of elite landed Catholic families, a segment of the Catholic body often overlooked in the existing historiography of these campaigns, the study adds nuance to understanding of the tensions and conflict within the Irish Catholic population and also provides new details of some aspects of the campaigns. Finally, the focus switches again to explore the Bellews’ educational, employment and travel strategies in Britain and on the Continent. This demonstrates how such mobility provided opportunity and reinforced their identity as members of an elite transnational class, which in turn provided both practical and psychological support in facing the challenges at home