List of subdivisions of County Dublin

County Dublin refers to a subdivision of Ireland occasioned by the Norman invasion of Ireland. This shire or county underwent further subsivisions as the territory was subinfeudated by the great barons among their vassals; these smaller areas were known as baronies. Under the government of the Kingdom of Ireland, baronies were in turn split into civil parishes. These also were split into the lowest recognised legal unit of land - the townland. In 1994 the former County Dublin, together with its administrative councils (Dublin County Council and Dublin Corporation), were formally abolished. New legal entities were created.

The Dublin Region is a region of the Republic of Ireland as recognised by the European Union. It is one of eight regions of the Republic of Ireland The region is under the administration of the Dublin Regional Authority (Irish Údarás Réigiúnda Átha Cliath). The region encompasses those areas previously defined by the county of Dublin, specifically following local government administrative areas:

For the purposes of elections to the Dáil, the boundaries of the constituencies must respect the overall boundaries of the Dublin Region. In defining such boundaries in legislation, no mention is made to County Dublin, only the Dublin Region under the remit of the Authority. No organ of the state now recognises the former county of Dublin.

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