Castlecoote was originally a mediaeval castle guarding a strategic crossing of the River Suck, possibly built by the McGerraghty family from nearby Fuerty.
The castle was given to Charles Coote, a successful soldier in the wars at the end of Queen Elizabeth's reign, in 1614. He improved and refortified the original castle and renamed it Castle Coote. By the second half of the seventeenth century the castle had fallen into ruins and a new dwelling was built within the walls. In the early 18th century Castlecoote passed into the hands of the Gunning family. Later in the 18th century the 1680's house was remodeled in the Palladian style and given an elaborate neo-classical interior but despite their powerful connections the Gunning family returned to relative obscurity.
Castlecoote House then changed hands with increasing frequency but the house was subsequently abandoned and became ruinous. In 1997, when bought by the present owner, Kevin Finnerty, Castlecoote House was a cavernous ruin, without floors, stairs or windows while the internal walls were crumbling away. He began a lengthy period of restoration and the house has been returned to its original splendour.