Louisa Jane Montagu Douglas Scott, Duchess of Buccleuch and Queensberry VA (26 August 1836 – 16 March 1912) was the daughter of James Hamilton, 1st Duke of Abercorn.

She was the paternal grandmother of Princess Alice, Duchess of Gloucester, and of Marian Louisa, Lady Elmhirst.

Louisa Jane Hamilton was born on Friday 26 August 1836 in Brighton, Sussex, England,[1] the third child of fourteen born to James Hamilton, 1st Duke of Abercorn, and the former Lady Louisa Russell, daughter of John Russell, 6th Duke of Bedford.

Lord Dalkeith was the eldest son of the Walter Montagu Douglas Scott, 5th Duke of Buccleuch, and his wife, the former Lady Charlotte Thynne.

She was buried on Wednesday 20 March 1912 in the Buccleuch family crypt in St. Mary's Church, Dalkeith Palace, Midlothian, Scotland.