Paintings of horses by Johann Georg de Hamilton who lived from 1672 to 1737. Born in Munich which was then part of the Southern Netherlands, he later moved to Vienna and then Berlin, ending up back in Vienna. Painted a lot of hunting scenes, too.

the-piebald-stallion-at-the-eisgruber-stud-johann-george-von-hamilton
“The Piebald Stallion at the Eisgruber Stud.” ca. 1707. In the public domain due to age. via https://fineartamerica.com/featured/the-piebald-stallion-at-the-eisgruber-stud-johann-george-von-hamilton.html
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“Cerbero.” ca. 1725. In the public domain due to age. via https://fineartamerica.com/featured/cerbero-johann-georg-von-hamilton.html
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“Gitano” ca. 1721-1726. Collections of the Kunsthistorisches Museum Wien, Wagenburg. Cc0 License 4.0. via http://www.kulturpool.at/plugins/kulturpool/showitem.action?itemId=270583573678&kupoContext=default

Paintings of Victorian horses working by British artist James Pollard (1792–1867).

"The Wokingham Stakes." 19th c. Oil on canvas. Signed.
“The Wokingham Stakes.” 19th c. Oil on canvas. Signed. Image © 2015 – 2019 BIDTOART. Fair use license. via https://bidtoart.com/en/fine-art/the-wokingham-stakes/191543
"Coursers Taking the Field at Hatfield Park, Hertfordshire, the Seat of the Marquess of Salisbury." Exhibited in 1824.
“Coursers Taking the Field at Hatfield Park, Hertfordshire, the Seat of the Marquess of Salisbury.” Exhibited in 1824. Collection of the Tate Gallery, London. Cc0 License 3.0. via https://www.tate.org.uk/art/artworks/pollard-coursers-taking-the-field-at-hatfield-park-hertfordshire-the-seat-of-the-marquess-t03434
"Epsom Races - The Betting Post." 19th c.
“Epsom Races – The Betting Post.” 19th c. In the public domain. via https://pixels.com/featured/epsom-races–the-betting-post-james-pollard.html