It was designed by Sir Robert Rowand Anderson for the 3rd Marquess in the late 1870s,[1] replacing an earlier house by Alexander McGill, which burnt down in 1877.

[3] The main part of the present house is a flamboyant example of 19th-century Gothic Revival architecture, built in a reddish-brown stone.

Mount Stuart's major features include the colonnaded Marble Hall at the centre of the main block and the Marble Chapel, which has an elaborate spired tower which is the tallest part of the building.

[4] Much of the furniture was custom-designed for the house by Robert Weir Schultz in the early years of the 20th century.

The Collection also houses archives, books, furniture, and silverwork reflecting the interests of the Bute family's various generations, including 25,000 books on topics including theology, botany, agriculture and Scottish history and literature.