Born at Montagu House, Whitehall, Westminster, London, into a family of four boys and three girls, William Henry Walter Montagu Douglas Scott was the eldest son of Walter Montagu Douglas Scott, 5th Duke of Buccleuch & 7th Duke of Queensberry and Lady Charlotte Anne Thynne, daughter of Sir Thomas Thynne, 2nd Marquess of Bath, and the Hon.

It was well presented but inside the neatly printed cover, there were just thirty-two blank pages,[4] making it an early empty book.

On Tuesday 22 November 1859, he married Lady Louisa Jane Hamilton in London, England.

They had six sons and two daughters: The Duke died at Montagu House, Whitehall, London, England on Thursday 5 November 1914, in his 83rd year.

He was buried on Tuesday 10 November 1914[7] in the family crypt of the Buccleuch Memorial Chapel in St. Mary's Episcopal Church, Dalkeith, Midlothian.