Louisa Caroline Baring, Baroness Ashburton (née Stewart-Mackenzie; 5 March 1827 – 2 February 1903) was a Scottish art collector and philanthropist who had close connections with several artistic and literary figures of the period.

In adolescence, she lived in Ceylon (now Sri Lanka), while her father was governor and then in 1841, the family moved to Corfu, Greece, when he became Lord High Commissioner of the Ionian Islands.

[1] Among her notable friends were Robert Browning, to whom she at one time unsuccessfully proposed marriage,[1][2] Thomas Carlyle, Edwin Landseer, whose attentions she rejected,[4] Florence Nightingale and Pauline, Lady Trevelyan.

[1] Lady Ashburton was known for amassing a large collection of art works and distributing them among her residences at Seaforth Lodge, Melchet Court in Hampshire, and Kent House in Knightsbridge, London.

Though no inventory existed, among the known works were sketches, watercolors and sculptures by Rubens, Mantegna, Rossetti, W. L. Leitch, Harriet Hosmer, Edward Lear, G. F. Watts, Marochetti and Titian.

[22] Lady Ashburton died of breast cancer on 2 February 1903, aged 75, at Kent House, Rutland Gardens, Knightsbridge, London.