The purpose of the project was to provide machine-readable economic and social history statistics relating to the whole of Ireland for the period 1821-1971. Further information about the project is available on the QUB Centre for Data Digitisation and Analysis website. The main tables are: Total number of Roman Catholics, Church of Ireland members, Presbyterians, Methodists and others grouped by counties. Total number of Roman Catholics, Church of Ireland members, Presbyterians, Methodists, Independents, Baptists, Quakers, Jews and others grouped by baronies and gender (1861 only). Please note: this study does not include information on named individuals and would therefore not be useful for personal family history research.