The name Kilcoursey is from Kilcoursey Castle (also called Lehinch Castle; near Clara), which is named for Kilcoursey townland (Irish Cill Chuairsí, "Cuairseach's church").[1]
In the early centuries of Christianity in Ireland, the family were known as Ó Catharnaigh (O'Kearney in the Anglicized form), from their chief, Tadgh O'Catharniagh, who died in 1084. Tadgh's extraordinary cunning had earned him the nickname "An Sionnach", which translated as "The Fox" in English. Subsequently, the Catharnaigh branch acquired this nickname as a distinct surname. The influence and power of the Foxes declined, due to conflict with rival Gaelic monarchs, and advancing control of English forces. However, even when their influence had diminished, they still retained considerable territory in Offaly, and became Barrons of Kilcoursey.[4]
↑Curley, Walter (2004). Vanishing Kingdoms, The Irish Chiefs and their Families. Dublin, Ireland: The Lilliput Press. pp.Pages 133–134. ISBN1843510561.
