Lieutenant-Colonel Llewellyn Wood Longstaff OBE FRGS (23 December 1841 – 20 November 1918) was an English industrialist and fellow of the Royal Geographical Society. He is best known for being the chief private-sector patron and financial angel of the Discovery Expedition to the Antarctic.
Llewellyn Longstaff was born in Wandsworth, London, on 23 December 1841. He married in 1873 Marie Lydia Sawyer, with whom he had 10 children, including mountaineer Tom George Longstaff. He owned a significant equity share in Blundell Spence & Co., a ₤400,000 firm based in Kingston upon Hull that crushed linseed oil to manufacture oil paint. He was also a member of several nongovernmental organizations, including the Freemasons, the Hull Chamber of Commerce and Shipping, and the Royal Geographical Society (RGS).
Longstaff's Society membership coincided with the presidency of longtime RGS leader Sir Clements Markham, whose dream was to organize a British expedition to the then-unknown Antarctic continent. Markham's initial efforts to lobby for funds were met with indifference in London; but Longstaff's friendship with Markham made it possible for the impecunious expedition plans to move forward, as the industrialist pledged in 1899 to donate ₤25,000 sterling. The British government then promised to appropriate ₤40,000 as matching funds, thus creating a budget to support the construction in 1900-1901 of a ship for the expedition, RRS Discovery. The ship, partly paid for by Longstaff, would be commanded by Markham's protégé Robert Falcon Scott.