Really interesting story.

Just before his death, Cheval received recognition from figures including André Breton, Robert Doisneau, and Pablo Picasso.[10] His work is commemorated in an essay by Anaïs Nin. In 1932, the German artist Max Ernst created a collage titled The Postman Cheval. ... In 1969, André Malraux, the minister of Culture, declared the Palais a cultural landmark and had it officially protected.