William Russell Flint was born in Edinburgh where he studied at the Royal Institution and served an apprenticeship as a lithographic artist. At the turn of the century he moved to London where he attended both Heatherley's School of Fine Art and Hammersmith School of Art, and worked for The Illustrated London News. After the First World War, in which he served in the Navy, he established himself as a painter of landscapes and figures, specialising in watercolours.
Having been elected an Associate of the Royal Society of Painters in Water-Colours in 1914 and a full Member in 1917, he served as President from 1936 to 1954. He was elected an Associate of the Royal Academy in 1924, became a full Member in 1933, and in 1962 he was one of only nine Royal Academicians to be honoured with an exhibition of his work in the Diploma Gallery during his lifetime.