The Westmorland or Westmoreland[1] was a 26-gun British privateer frigate, operating in the Mediterranean Sea against French shipping in retaliation for France's opposition to Great Britain in the American Revolutionary War.

The most notable incident in the life of the Westmorland occurred shortly after she sailed for Britain from Livorno under Captain Michael Wallace late in 1778, carrying a large monetary payment for her inbound cargo of salt cod from Newfoundland (Livorno was a trade hub for this commodity), food goods,[2] and 57 crates of artistic objects collected by Grand Tourists such as the Duke of Gloucester, Sir John Henderson and the Duke of Norfolk.

[5] At Málaga her artistic contents were passed on from the French government to two trading companies with links to Ireland, despite Wallace's protests that the ship was full of "extremely precious goods" (the French had already seized her cash cargo), and the Spanish king was informed by his prime minister, José Moñino, 1st Count of Floridablanca, of the arrival of the art works.

Upon Spain's formal declaration of war, king Charles III secretly bought the art from a syndicate of Madrid merchants for 360,000 silver reales (a discount on their original asking price of 600,000 gold doubloons, but still a considerable sum) and had it brought by cart to the capital.

[6] Recent research into the original lists in Spain has made more precise identification possible,[7] cataloguing for example items from the collection of Francis Basset, 1st Baron de Dunstanville, including his two portraits.