This room is one of three interconnected libraries in the house, each named after a different colour - Blue, Red and Purple - which were the original wall colours. There is also a fourth modern repository, which adjoins the Bute Collection Archive at Mount Stuart, known as Library 4. This fourth library was installed by Johnny, 7th Marquess of Bute, and is home to the book collections accumulated at Dumfries House that were brought to Mount Stuart in 2004. Over 27,000 volumes are housed in the libraries at Mount Stuart, dating from 1477 to the present day.

Windows

H W Lonsdale’s stained glass windows depict the coats of arms of the towns of Dumfries and Ayr, both of which have a connection to the Earldom of Dumfries.

Lonsdale also produced unexecuted designs for the windows facing the lawn, depicting the Four Evangelists reading. Perhaps these were intended to reflect the fact that this library houses the 3rd Marquess’s large and important collection of theological works – the 3rd Marquess being a great religious scholar who translated the Roman Breviary from Latin into English. The Library also includes botanical works relating to the interests of the 3rd Earl of Bute in the 18th century.

Woodwork

The ceiling - another example of the work of the Bute Workshops in Cardiff - would have been decorated in rich colours in a similar style to the ceilings in the Family Bedroom and the Horoscope Room, but again this work was not begun. In 1912 the original bookcases and panelling were replaced by the ornate woodwork we see today, which was designed by Sir Robert Rowand Anderson and executed in the Cardiff workshops. This includes the heraldic devices of the 4th Marquess of Bute and his wife Augusta Bellingham and, carved into the fireplace mirror surround, a group of mischievous looking monkeys puzzling over the Books of Knowledge.

Furniture & Decorative Art

A George III ormolu-mounted kingwood longcase regulator clock in a Louis XV style case, the glazed polished steel dial showing the day of the week, month of the year, phase of the moon and astronomical dials.

A Regency mahogany desk, with rectangular top inset green leather-lined writing surface. It is likely made by Gillows of Lancaster and London. Gillow (1730 - 1840) was one of the most respected furniture makers of the 18th and 19th centuries, selling to upper and middle-class clients across Britain and overseas.

Two oak tables with twisted legs designed by Scottish architect Sir Robert Lorimer. Lorimer had been an assistant of Sir Robert Rowand Anderson at the time Anderson was working on Mount Stuart.

Model of a Maltese 17th century ship with the name plaque 'Korcula'. Possibly connected to Korcula, an island in the Dalmation archipelago, part of modern Croatia. The Isle of Bute has twinning links with with Korcula, developed by Sir Fitzroy MacClean, former MP for Argyll and Bute. During the 1991 civil war in Yogoslavia, Sir MacClean arranged medical aid for Korcula with donations from the community of Rothesay and Bute.

Paintings

The Purple Library houses a group of portraits depicting members, friends and associates of the Bute family from the 17th to the mid 19th centuries. Several of these portraits were in the original Mount Stuart, the Georgian mansion destroyed by fire in 1877.