Lord Ribblesdale, sometimes known as The Ancestor, is a portrait in oils on canvas by John Singer Sargent of Thomas Lister, 4th Baron Ribblesdale, completed in 1902. The full-length portrait depicts Lord Ribblesdale in his hunting clothes. It measures 258.4 cm × 143.5 cm (101.7 in × 56.5 in) and has been held by the National Gallery in London since 1916.
Thomas Lister became the fourth (and last) Baron Ribblesdale on the death of his father in 1876, when he was aged 22. He supported the Liberal Party in the House of Lords, served as a lord-in-waiting at the Royal court, and was a trustee of the National Portrait Gallery and the National Gallery He was Master of the Queen’s Buckhounds from 1892 to 1895.
Although Sargent was already a popular society portraitist, the painting was not commissioned by the sitter. Rather, Sargent saw Ribblesdale speaking in public in 1894, and the artist approached Ribblesdale to propose painting his portrait. However, Sargent did not start the proposed portrait until 1899; he completed it in 1902.