Lord Francis Douglas Marquess of Queensberry; a younger brother, Lord Archibald Edward Douglas (1850–1938), who became a clergyman; and a younger brother and sister, the twins Lord James Douglas (d. 1891) and Lady Florence Douglas (1855–1905), who married Sir Alexander Beaumont Churchill Dixie, 11th Baronet. He was an uncle of Oscar Wilde's lover Lord Alfred Douglas, and a younger brother of John Douglas, 9th Marquess of Queensberry. In 1858, Douglas's father, Lord Queensberry, died in what was reported as a shooting accident, but his death was widely believed to have been suicide. In 1862, his mother, Lady Queensberry, converted to Roman Catholicism and
Lord Alfred Douglas the Jews, attributing them qualities and methods which are really much more typically English than Jewish", and then indicate the country only had itself to blame if the Jews came in and trampled on it. The historian Colin Holmes indicated that while "Douglas had been to the forefront of anti-semitism in the early 1920s, he was quite unable to come to terms with the vicious racist anti-semitism in Germany" under the Nazis. Douglas started his "litigious and libellous career" by obtaining an apology and fifty guineas each from the Oxford and Cambridge university magazines "Isis" and "Cambridge" for defamatory references