http://homepage.eircom.net/~seanjmurphy/nai/puboffs.htm#Tithe
Tithe was a tax payable on agricultural land to the Established Protestant Church of Ireland, and was naturally greatly resented by non-members of that denomination. A series of acts were passed from 1823 onwards in an effort to make the method of calculating the tax fairer, but it was eventually to be generally abolished in 1869 (though it survived into this century in some cases as a rent charge). Under the 1823 Act, Commissioners were appointed to value land in each parish, and books listing tithe-payers and quantities of land were compiled for most parishes, generally at dates between 1823-38. Having been first deposited with the Irish Land Commission, the Tithe Applotment Books were transferred in the 1940s to the Public Record Office of Ireland and the Public Record Office of Northern Ireland.
Because of the destruction of most pre-1901 census records, the Tithe Applotment Books are an important census substitute, listing on average about 40 per cent of heads of families. As the originals have been withdrawn for conservation reasons, the Tithe Books must be viewed in microfilm copy form. The National Library of Ireland and some other repositories also hold microfilm copies of the Tithe Books, while the Public Record Office of Northern Ireland as indicated holds the originals of the books relating to the Six Counties. Refer to List of Tithe Applotment Books on microfilm, and National Library of Ireland, Index of Surnames. See also Tithe Defaulter's Lists, page 18.
Tithe
Applotment(taken 1823-38)
The tithe was a land-based tax exacted from rural
Ireland between 1823 and 1837. The tax did not apply to inhabitants of the
cities or larger towns. Though taken from people of all faiths, the tithe was
used to support the Church of Ireland in rural areas. Tithe Applotment books
record the name of the head of the household and the value of the property.