Clementine-Hélène Dufau (18 August 1869, Quinsac - 18 March 1937, Paris) was a French painter decorative artist, poster designer and illustrator.
Her father was an entrepreneur of Basque ancestry who made a fortune during a trip to Cuba and married the daughter of a vineyard owner when he returned. The vineyard, Le Château de Clauzel, is still in business.
She was in poor health as a girl and had to spend many hours in bed, during which she began to draw. After her sisters were all married, she wanted to study art. Her parents decided to sell their interest in the vineyard and moved to Paris with her in 1888.
She enrolled at the Académie Julian; studying with William Bouguereau and Tony Robert-Fleury. In 1895, she exhibited at the Salon des Artistes Français and was awarded a prize for her painting, L'Amour de l'Art. As a result, she began to receive orders for advertising posters, beginning with one for the Bal des Increvables at the Casino de Paris, followed by one to announce the launching of La Fronde, a journal founded by Marguerite Durand in 1897. The following year, she became a member of the Société des Artistes Français and obtained a scholarship to study in Spain.
By 1905, she was a well-established artist; working with Edmond Rostand and decorating his "Villa Arnaga" in Cambo-les-Bains. Her mother's sudden death plunged her into solitude and she developed what she herself described as a mad passion for Edmond's youngest son Maurice, who was still a teenager and openly homosexual. This tormented relationship lasted for several years.