Major media reports indicate that the castle was initially built in 1081 by the Normans to protect Cardiff. It underwent significant renovations in 1848 under John Crichton-Stuart, the 3rd Marquess of Bute, who commissioned architect William Burges to redesign the interiors. Burges added lavish furnishings and opulent details, but died in 1881 from a chill he caught during a visit to the castle. His assistant, William Frame, completed the interiors by 1891. However, the Marquess seldom visited the castle after its completion, and it fell into neglect.
After the Marquess’s death in 1900, the castle passed to his wife and later to another descendant. In 1950, it was placed under the care of the Ministry of Works, and it received official listed building status in 1963. Since the 1980s, Cadw has managed the castle’s preservation. The castle is open to the public and is frequently voted one of the most beloved buildings in Wales.