Seraphine de Senlis
Séraphine Louis was born in Arsy (Oise) on September 3, 1864. Her father was a manual laborer and her mother came from a farmworking background. Séraphine's mother died on her first birthday and her father, who remarried, also died before she was seven; at which point, she came under the charge of her eldest sister. She first worked as a shepherdess but, by 1881, she was engaged as a domestic worker at theconvent of the Sisters of Providence in Clermont (Oise). Beginning in 1901, she was employed as a housekeeper for middle class families in the city of Senlis.
Alongside her arduous day jobs, Séraphine painted by candlelight, largely in secret isolation, until her considerable body of work was discovered in 1912 by German art collector Wilhelm Uhde. While in Senlis, Uhde saw a still-life of apples at his neighbor's house and was astonished to learn that Séraphine, his housecleaner, was the artist. His support had barely begun to lift her horizons when he was forced to leave France in August 1914; the war between France and Germany had made him an unwelcome outsider in Senlis, much as Séraphine was, given her eccentric persona. They only reestablished contact in 1927 when Uhde – back in France and living in Chantilly - visited an exhibition of local artists in Senlis and, seeing Séraphine's work, realized that she had survived and her art had flourished. Under Uhde's patronage, Séraphine began painting large canvases as large as two meters high, and she achieved prominence as the naïve painter of her day. In 1929, Uhde organized an exhibition, "Painters of the Sacred Heart," that featured Séraphine's art, launching her into a period of financial success she had never known - and was ill prepared to manage. Then, in 1930, with the effects of the Great Depression destroying the finances of her patrons, Uhde had no choice except to stop buying her paintings.
In 1932, Séraphine was admitted for "chronic psychosis" to the psychiatric ward of a geriatric hospital at Clermont, where her artistry found no outlet. Although Uhde reported that she had died in 1934, Séraphine actually lived until 1942 in a hospital annex at Villers-sous-Erquery, where she died friendless and alone. (Some sources  still state she died in 1934.) She was buried in a common grave.
Uhde continued to exhibit her work: in 1932, at the exhibition "The Modern Primitives" in Paris; in 1937-38 in an exhibition titled "The Popular Masters of Reality" which showed in Paris, Zurich, and New York (at MoMA); in 1942, at the "Primitives of the 20th Century" exhibit in Paris, and finally, in 1945, in a solo exhibition of her work in Paris. Her paintings are housed in the Musée Maillol in Paris, the Musée d'art de Senlis, the Musée d'art naïf in Nice, and the Musée d'Art moderne Lille Métropole in Villeneuve-d'Ascq.
Biography from wikipedia