|From the 17th century, the civil parishes were based on the early Christian and medieval monastic and church settlements. They were used widely for various surveys. By the 19th century the boundaries of the the civil parishes was well established. As the population grew, however, new parishes were created by either subdividing larger ones or by moving townlands from nearby parishes. The civil parish basically covered the same area as the Church of Ireland. On the other hand, the Roman Catholic Church, due to the Reformation of the 16th century, had to adapt itself to a new structure centered on towns and villages. There were 2,508 civil parishes in all of Ireland. They do not respect either barony or county lines. The civil parishes are the basic geographical units used for the Griffiths Valuation (1851-52), Tithe Applotment (1823-38), tax records, censuses, etc. They have about the same boundaries as the parishes for the Church of Ireland but different from the parishes of the Catholic Church.