Partly Bute was indulging his passion for medieval buildings, no doubt inherited from his father, who had restored and redecorated Cardiff Castle and Castell Coch.
Yn rhannol, roedd Bute yn ymroi i’w frwdfrydedd dros adeiladau canoloesol, a etifeddwyd gan ei dad, mae’n siŵr, a oedd wedi adfer ac ailaddurno Castell Caerdydd a Chastell Coch.