The vast majority of Irish census records prior to 1901 no longer exist. Consequently, as Brian Mitchell explains in his New Pocket Guide to Irish Genealogy, census substitutes are of great importance to Irish researchers. Perhaps the most important, and certainly the most famous, substitute is Griffith’s Primary Valuation. Conducted between 1848 and 1864, the Valuation provides the amount of rates each household had to pay towards the support of the poor within their poor law union. Each Valuation names every head of household and occupier of land in Ireland, versus a townland or street address in Ireland. Griffith’s Valuation thus details the land occupier’s name; the landlord’s name; description of property; size of farm (if applicable); and ratable valuation of any buildings and land.
Mr. Mitchell provides the following sample entry from Griffith’s and an explanation of how to interpret and utilize the results.