Smarmore Castle was first officially mentioned[1] in 1320 as the seat of the Taaffe family.
[2] The Taaffe family, originating from Britain, lived in Smarmore Castle up to the 1980s.
After the Taaffe family sold the castle it was converted into a guest house.
The Smarmore Castle Private Clinic, a drug and alcohol treatment centre, opened in 2016.
[3] The name Smarmore is seen to have its origin in an Irish language legend known as Táin Bó Cúailnge (The Cattle Raid of Cooley).