[2] His father, Francis Scott, died of smallpox at the age of 29, just one year before the death of Henry's grandfather, the 2nd Duke of Buccleuch.

[1] Educated at Eton College,[2] through his stepfather Charles Townshend, Henry was given the opportunity to travel abroad with Adam Smith as his tutor from 1764 to 1766.

Elizabeth's maternal and paternal grandparents were, respectively, Sir John Montagu, 2nd Duke of Montagu and Lady Mary Churchill, and George Brudenell, 3rd Earl of Cardigan and Lady Elizabeth Bruce.

Seventeen years later, in 1766, King George III created him Duke of Montagu and Marquess of Monthermer.

Elizabeth inherited only the unentailed Montagu assets, which included Boughton House in Weekley, Northamptonshire.

William Douglas, 4th Duke of Queensberry never married; when he died on 23 December 1810, his peerages and entailments passed to his 2nd cousin once removed, Sir Henry Montagu Scott, 3rd Duke of Buccleuch, through Sir Henry's grandmother, Lady Jane Douglas, Queensberry's first cousin once removed.

He was buried in the family crypt of the Buccleuch Memorial Chapel in St. Mary's Episcopal Church, Dalkeith, Midlothian.