The first quarter of the nineteenth century was a time of great change and uncertainty in Ireland. The rebellion of 1798 was followed in 1801 by the Act of Union, which brought about legislative and ecclesiastical union from Britain. If the Church of Ireland was ever to make a success of its mission in-Ireland, it was in these early years of the nineteenth century. On the eve of this opportunity Thomas Lewis O’Beime, an Irish convert and former Roman Catholic seminarian, was translated from the diocese of Ossory to Hie see of Meath. Availing of compensation monies, ecclesiastic bursaries and gifts or loans from the trustees of the Board of First Fruits, the bishop began twenty-five years of infrastructural change and pastoral reform on a scale not seen in any diocese in the history of the reformed church. This study has not one, but two main concerns. The first is to set out, for the first time, a full as possible account of the infrastructural changes instituted and maintained by Bishop O’Beime during his time in the diocese of Meath. The second is to record by architectural inventory, what remains of the churches built or rebuilt during his episcopate. The latter is particularly pressing, as already, a number of those buildings no longer dress the landscape and several others, due to their current dilapidated state, will soon disappear. In order to gain an understanding of this spate of church building and reform, it is first necessary to investigate the bishop himself, his background, career, views, political and religious associates. Hence, O’Beime is the subject of the first chapter. To fully appreciate the scale of O’Beime’s work in Meath and provide some historical context, the second chapter sets out the extent of the diocese and provides an overview of its history. This includes land distributions made at the time of the dissolutions, the resulting arrangement of parish patronage and tithe impropriations and the role of some of O’Beime’s episcopal predecessors. Chapters three and four concentrate on the infrastructural changes brought about by O’Beime. Chapter five examines the contribution of parish patrons, tithe impropriators, congregations and parishioners at large.