County Down
The Historical Mapping Atlas provides population data for all 32 counties within the Island of Ireland from 1841 to 2002. Data is available at Electoral Division level, at a consistent set of 3432 EDs, which is based on the 1851 Electoral Division boundary set. The data used in this population atlas is from 16 censuses, taken in both the Republic and the North of Ireland between 1841 and 2002. 
The boundaries used in this atlas are based on the historic Electoral Division boundaries created in the second half of the 1840s. Here we have created a boundary set of 3,432 EDs (Electoral Divisions) in accordance with those set out in the 1851 census.
Additional research has also been undertaken by the National Centre for Geocomputation (NCG) that examines the spatial variations in population change at electoral division (ED) level and the extent to which features of the social and natural landscape can be identified and statistically analysed as determinants of population change. See the NCG website for further details.
All maps produced in this Irish Historical Population Change Atlas are produced under the National Centre for Geocomputation (NCG) mapping license: Ordnance Survey Ireland Licence Number EN. 0072711 © Ordnance Survey Ireland / Government of Ireland.