James Francis Harry St Clair-Erskine, 5th Earl of Rosslyn (16 March 1869 – 10 August 1939), styled Lord Loughborough until 1890, was a Scottish soldier, author and aristocrat.

[5] His mother, the dowager Countess of Rosslyn, survived his father by over 40 years before her death at Regent's Park, London, in December 1933.

[1] From 1890 to 1897, he was Captain of the Fifeshire Light Horse Volunteers, serving with Alexander Thorneycroft's Mounted Infantry during the Second Boer War where he was taken prisoner twice,[6] which he wrote about in his book Twice Captured.

[3] Lord Rosslyn was a notorious gambler, betting £15,000 on Buccaneer to win the Manchester Cup, which lost.

He played the roulette tables at Cannes and Monte Carlo, which he wrote about in his autobiography My Gamble With Life.

[9] In 1908, Rosslyn and Sir Hiram Maxim were in the news for a gambling duel in Monte Carlo to "break the bank".

[10] On 19 July 1890, Lord Rosslyn was married to Violet Aline Vyner (d. 1945), the second daughter and co-heiress of Robert Charles de Grey Vyner of Gautby Hall and Newby Hall by his wife Eleanor Shafto (a daughter of Rev.