The painting depicts a tow-horse being ferried across the river Stour in Suffolk, just below Flatford Lock at a point where the tow-path switched banks. Constable, who described the scene as "as placid represtentation of a serene, grey morning, summer," went on in later years to comment: "There are generally in the life of an artist perhaps one, two or three pictures, on which hang more than usual interest-- this is mine." The painting was well received when it was shown at the Royal Academy exhibition of 1819, and it was purchased by Constable's friend Archdeacon John Fisher. Constable bought back the painting in 1829 and kept it the rest of his life. There is a full-scale oil sketch for The White Horse in the National Gallery of Art, Washington.
Source: Art in The Frick Collection: Paintings, Sculpture, Decorative Arts, New York: Harry N. Abrams, 1996.
Cocktails with a Curator: Constable's "The White Horse"