Rathfarnham

Located within the historical baronies of Rathdown and Uppercross, Rathfarnham village originally developed around a fortification overlooking a ford on the River Dodder. From the medieval period, Rathfarnham was on the perimeter of the Pale (the area of Anglo-Norman influence in Ireland, centred on Dublin), and a number of defensive structures were built in the area. Rathfarnham Castle, a fortified house, was built in the late 16th century. Developed around these structures, by the 19th century there were a number of mills operating in the area, and Rathfarnham was still somewhat rural by the early 20th century. During the 20th century, with the expansion of metropolitan Dublin, Rathfarnham became a largely residential suburban area.

The population of all electoral divisions labelled as Rathfarnham was 23,276 as of the 2022 census.