An electoral division is the smallest legally defined administrative areas in Ireland for which small area population statistics are published from the Census. There are a total of 3,440 electoral divisions in Ireland. They are used to define local electoral areas for elections to county and city councils and to define constituencies in elections to Dáil Éireann. Until 1994, they were known as district electoral divisions in the county council areas and wards in the five county boroughs which were then in existence. Electoral divisions are local administrative units within the NUTS system of the European Union.
Origins
District electoral divisions originated as subdivisions of poor law unions, grouping a number of townlands together to elect one or more members to a Poor Law Board of Guardians. The boundaries of district electoral divisions were drawn by a Poor Law Boundary Commission, with the intention of producing areas of roughly equivalent "rateable value" as well as population. This meant that while DEDs were almost always contiguous, they might bear little relation to natural community boundaries. The Local Government Act 1898 established a system of county councils and urban and rural district councils and the district electoral divisions were then used to elect members to the district councils, with groups of DEDs combining to elect members to county councils. The introduction of the single transferable vote at the 1920 local elections meant that district electoral divisions were grouped together to elect a number of members to the relevant councils. Rural district councils were abolished in all but Dublin by the Local Government Act 1925, and were abolished in Dublin by the Local Government Act 1930. This meant that district electoral divisions no longer had any electoral purpose in their own right. However, they continued to be used for other administrative purposes such as low-level census divisions, and definitions of local electoral areas and constituencies, although in some cases these will cut across EDs. Outside Dublin, most DED boundaries have remained unchanged since the 1850s. In County Dublin, however, the rapid increase in population of the city's suburbs has meant that district electoral divisions have been periodically redrawn so as to produce smaller divisions of a convenient size. In addition, the expansion of the city boundaries of Cork, Limerick and Waterford and the establishment of Galway as a county borough in 1985, required the redrawing of ward boundaries within the cities, and the consequent adjustment of the DEDs affected by the boundary changes. Because the boundaries of district electoral divisions have largely remained unchanged since the nineteenth century, their populations vary widely, ranging from 32,305 for the electoral division of Blanchardstown–Blakestown in Fingal to 16 for the electoral divisions of Arigna in County Leitrim. To maintain confidentiality, 32 EDs with low population are amalgamated into neighbouring EDs in the presentation of census data. District electoral division boundaries also tend to bear little relation to the boundaries of natural communities in rural Ireland such as parishes, with the result that most people will have little or no idea which electoral division they live in.
After the partition of Ireland and the establishment of Northern Ireland in 1921, the new Ulster Unionist Party –government redrew district electoral division boundaries in the six counties of the region. The government and its supporters claimed that this redrawing was necessary because population changes had caused discrepancies in the population of DEDs and it was necessary to change the boundaries to equalise electorates. Irish nationalists, on the other hand, claimed that the boundaries were being redrawn to gerrymanderlocal councils, producing unionist-majority councils in areas where the majority of the population was nationalist. Certainly, the effect of the redrawing of boundaries was to dramatically reduce the number of local councils under nationalist control, and examination of the archives of the Northern Ireland Government has shown that the Ministry of Home Affairs worked closely with local Unionist associations to produce favourable results for the UUP. With the reform of local government in Northern Ireland in 1973, both county councils and urban and rural district councils were abolished and replaced by a smaller set of district councils. These councils were divided into wards, each ward containing a number of townlands or parts of townlands. As a result, district electoral divisions no longer exist in Northern Ireland and the groups of wards used for single transferable vote are known as "district electoral areas".