He is a descendant of James, Duke of Monmouth (9 April 1649 – 15 July 1685), the eldest illegitimate son of Charles II and his mistress, Lucy Walter, and more remotely in a direct male line from Alan of Dol, who arrived in Britain in 1066 with William the Conqueror.

[6][7] In 1973, his father inherited the Dukedoms of Buccleuch and Queensberry, and Scott took the courtesy title Earl of Dalkeith, having previously been styled Lord Eskdaill.

As Earl of Dalkeith, he had a brief term on the board of Border Television from 1989 to 1990, and in 1994 he joined the Millennium Commission as the representative for Northern England.

He was made a Knight Commander of the Order of the British Empire (KBE) in the 2000 New Year Honours for his services to the Millennium Celebrations,[8] leaving the commission in 2003.

The art collection of the Dukes of Buccleuch is of great significance, and the recovery of the stolen Leonardo da Vinci painting Madonna of the Yarnwinder from the collection, valued at 30 million GBP, in a raid on the offices of a prestigious law firm captured public attention in 2007.

[9] In 2008 a painting in the family collection at Boughton House, a rare portrait of the young Queen Elizabeth I of England, was discovered.

Through his paternal great-grandmother, Lady Sybil Evelyn de Vere Beauclerk - daughter of William Beauclerk, 10th Duke of St Albans (15 April 1840 – 10 May 1898) and his first wife, Sybil Mary Grey (28 November 1848 – 7 September 1871), granddaughter of Charles Grey, 2nd Earl Grey - Scott is also a descendant of Charles Beauclerk, 1st Duke of St Albans (8 May 1670 – 10 May 1726), another illegitimate son of King Charles II of England and his mistress Nell Gwyn.

One of their forebears, Duncan McNeill, 1st Baron Colonsay, FRSE (20 August 1793 – 31 January 1874), had been Lord Advocate of Scotland.