She and her sister were independently wealthy, their fortune inherited from the businesses created by their grandfather, the industrialist David Davies.
Davies and her sister created one of the most important private collections of art in Britain and donated their total of 260 works to what is now the National Museum Wales in the mid-20th century.
In particular, they purchased many works by the Impressionists and post-Impressionists, although they also acquired holdings of 20th-century modern artists, such as Josef Herman, Oskar Kokoschka, Augustus John, Stanley Spencer, Frank Brangwyn, and Eric Gill.
[2] Gwendoline and Margaret Davies bought the mansion of Gregynog just after the First World War, following long discussions with their lifelong friend Thomas Jones,[3] and set up an arts centre there.
The festivals played host to important composers and other musical figures of the period, including Ralph Vaughan Williams, Edward Elgar, Gustav Holst, "the conductor Adrian Boult, and the poet Lascelles Abercrombie; and performers including Jelly d'Arányi and the Rothschild Quartet.
These works were re-examined for the BBC TV programme Fake or Fortune?,[7] and in an episode broadcast in 2012 they were reinstated as genuine Turners.