Clonalis House (Irish:Teach Chluain Mhalais) is an historic manor house inCastlerea,County Roscommon,Ireland, and the ancestral home of theO'Conor Don, who are direct descendants ofCathal Crobhdearg Ua Conchobair,King of Connacht, a younger brother ofRuaidrí Ua Conchobair, the lastHigh King of Ireland.
The current building was constructed in 1878 byCharles Owen O'Conor as a replacement for an earlier house on the same site which was frequently damaged by flooding. Built of mass concrete, its design byFrederick Pepys Cockerell is of a mixture of styles drawing on the traditions ofItalianate andQueen Anne Style architecture.
Its history reflects the turbulence ofIrish history, having once been occupied by theIrish Republican Army before it was shelled and captured by Free State Forces during theIrish Civil War. Some 100,000 volumes are contained in the family archives and library of the O'Conor Don which are still held at Clonalis House, making it a valuable repository of Irish history.
53°46′00″N8°30′00″W / 53.7667°N 8.5000°W /53.7667; -8.5000
