Art dealer in the context of Louis Finson

Theodorus "Theo" van Gogh (Dutch: [teːjoːˈdoːrʏs ˈteːjoː vɑŋ ˈɣɔx]; 1 May 1857 – 25 January 1891) was a Dutch art dealer and a younger brother of Vincent van Gogh. His support of his older brother's artistic ambitions and well-being allowed Vincent to devote himself entirely to painting. As an art dealer, Van Gogh played a crucial role in introducing contemporary French art to the public.

Van Gogh died at the age of 33, six months after his brother's death at age 37. Van Gogh owned almost all of his brother's artwork. His widow, Johanna van Gogh-Bonger, worked to promote the work of Vincent and keep the memory of her husband alive. In 1914, Van Gogh's remains were buried next to those of his brother Vincent.

Goupil & Cie is an international auction house and merchant of contemporary art and collectibles. Jean-Baptiste Adophe Goupil founded Goupil & Cie in 1850. Goupil & Cie became a leading art dealership in 19th-century France, with its headquarters in Paris. Step by step, Goupil established a worldwide trade in fine art reproductions of paintings and sculptures, with a network of branches and agents in London and other major art capitals across Continental Europe as well as in New York City and Australia. Les Ateliers Photographiques, their workshop north of Paris, in Asnières, was instrumental in their expansion from 1869. The leading figure of Goupil & Cie was Jean-Baptiste Adolphe Goupil (1806–1893). His daughter Marie married the French artist Jean-Léon Gérôme.

Johanna Gezina van Gogh-Bonger (4 October 1862 – 2 September 1925) was a Dutch editor who translated the hundreds of letters of her first husband, art dealer Theo van Gogh, and his brother, painter Vincent van Gogh.

Van Gogh-Bonger played a key role in the growth of Vincent van Gogh's posthumous fame.

Portrait of William Ewart Gladstone is an 1879 portrait painting by the British artist John Everett Millais. It depicts the politician William Ewart Gladstone who served as Prime Minister four times. It was one of a series of portraits of leading figures Millais produced during the era, including his Portrait of Benjamin Disraeli featuring Gladstone's political rival. The work was initiated by Millais himself, rather than being commissioned and was then bought for a thousand pounds by the art dealer William Agnew who sold it ten days later to the Duke of Westminster.

The painting was displayed at the Royal Academy Exhibition of 1879 at Burlington House in London. Louisa Knightley described It as "undoubtedly the picture of the year" while Gladstone himself considered it a "a very fine work". It was A mezzotint was produced by the engraver Thomas Oldham Barlow, who submitted a version as his diploma work when elected to the Royal Academy of Arts in 1881. The original painting has been in the collection of the National Portrait Gallery since 1957, having previously been in the Tate Gallery.

Charles Augustus Howell (10 March 1840 – 21 April 1890) was a Portuguese-British art dealer and alleged blackmailer who is best known for persuading the poet Dante Gabriel Rossetti to dig up the poems he buried with his wife Elizabeth Siddal. His reputation as a blackmailer inspired Arthur Conan Doyle's Sherlock Holmes story "The Adventure of Charles Augustus Milverton".

Samuel Siegfried Bing (26 February 1838 – 6 September 1905), who usually gave his name as S. Bing (not to be confused with his brother, Samuel Otto Bing, 1850–1905), was a German-French art dealer who lived in Paris as an adult, and who helped introduce Japanese art and artworks to the West and was a factor in the development of the Art Nouveau style during the late nineteenth century.

The Grafton Galleries, often referred to as the Grafton Gallery, was an art gallery in Mayfair, London. The French art dealer Paul Durand-Ruel showed the first major exhibition in Britain of Impressionist paintings there in 1905. Roger Fry's two famous exhibitions of Post-Impressionist works in 1910 and 1912 were both held at the gallery.

Paul Durand-Ruel (French pronunciation: [pɔl dyʁɑ̃ ʁɥɛl]; 31 October 1831 – 5 February 1922) was a French art dealer associated with the Impressionists and the Barbizon School. Being the first to support artists such as Claude Monet, Camille Pissarro, and Pierre-Auguste Renoir, he is known for his innovations in modernizing art markets, and is generally considered to be the most important art dealer of the 19th century. An ambitious entrepreneur, Durand-Ruel cultivated international interest in French artists by establishing art galleries and exhibitions in London, New York, Berlin, Brussels, among other places. Additionally, he played a role in the decentralization of art markets in France, which prior to the mid-19th century was monopolized by the Salon system.