Within the grounds of the house sits the church of St. Cadoc, which is possibly of late medieval origin.
[4] By 1850, the house was ‘playfully crenellated’ with a central pediment” [2] In 1876, the house was remodelled by Morgan Stuart Williams,[2] who later went on to restore St Donat's Castle[1] This ‘overwhelmed’ the work of 1850, and included the addition of a new front range dominated by a ‘remarkable top heavy Elizabethan gallery across the whole front’ of 94 feet.
[2] In 1868, Williams had rejected earlier plans by John Norton for a new house in Gothic style with a tower.
[citation needed] Part of the Williams family remained in Wales until 2015 living in Llanharan House.
[9] In the fifteenth century, Aberpergwm House was the home of Rhys ap Siancyn and his descendants, the most prominent of the poets’ patrons in Glamorgan during the period.
[11] The house is listed Grade II by Cadw and is undergoing extensive building work[citation needed] to conserve its important historical contents and structure.