The Tithe Applotment Books are a vital source for genealogical research for the pre-Famine period, given the loss of the 1821-51 Census records. They were compiled between 1823 and 1837 in order to determine the amount which occupiers of agricultural holdings over one acre should pay in tithes to the Church of Ireland (the main Protestant church and the church established by the State until its dis-establishment in 1871).
There is a manuscript book for almost every civil (Church of Ireland) parish in the country giving the names of occupiers of each townland, the amount of land held and the sums to be paid in tithes. Because the tithes were levied on agricultural land, urban areas are not included. Unfortunately, the books provide only the names of heads of family, not other family members.
The books have been digitally imaged, and a database giving surname, forename, county, parish and townland created. All of these fields can be searched, and there is also a browse facility, which allows users to survey entire parishes and townlands.
The population of Ireland was recorded in 1841 as 8.2 million. It would have been somewhat less than this during the 1820s and 1830s, when the Tithe Applotment Books were compiled.
The books for Northern Ireland are in the held in the Public Record Office of Northern Ireland, but there are microfilm copies in the National Archives which can be consulted in our Reading Room.