Louis Thomson was the signing name for painter and printmaker Louisa Emily Thomson, born in Kandy, Ceylon (now Sri Lanka) in 1883. She studied art in Rome and London, finally settling in England. She learned lithography from Ernest Jackson and joined the Senefelder Club. Thomson created both monochrome and color lithographs and worked in etching as well. She was a member of the Los Angeles-based International Society of California Printmakers.

Exhibitions include the Internationale di Belle Arti della Societa Amatouri e Cultori, Rome, Italy, 1908; and the Prima Esposizione Internazionale d'Arte della "Secessione", Rome, 1913. She exhibited regularly with the Royal Academy and the Society of Women Artists. Her work is included in the National Gallery of Victoria, Melbourne, Autralia.

Louisa Emily Thomson died in 1962 in England.