Jean-Pierre Haag is the son of Jean Haag, German mechanics worker established in Elbeuf (Normandy) and Geneviève Maloizel. He was originally part of the Normandy Painters Colony. All of his life, he kept a property in this area.
He joined the Ecouen Painters Colony in 1870 and settled down at 29 rue de Paris (currently being rue du Maréchal Leclerc). He became student of Pierre Edouard Frère and Léon Dansaert. Soon after, he married Ernestine Juliette Confais. They had several children, including Gaston. At their christening, either Theophile Emmanuel Duverger, Auguste Schenck or Charles Edouard Frere were present.
In 1870, he exhibits in Paris for the first time , showing a painting named “Intérieur de forge à Villiers-le-Bel” (inside a forge workshop in Villiers-le-Bel). He became to be known in 1877 and is invited there in 1895.
Like most of the other Artists of Ecouen, in his work, Jean-Pierre Haag has shown the country lifestyle, some simple works and common life sceneries.
One of his major artworks “La gardeuse d’enfants en Normandie” (the babysitter in Normandy) has been exhibited in 1980 at the Paris Grand Palais. In April 1989, “Le jeu de dominos” (the domino game) has been shown in London. Both of them are belonging to the Louviers museum (Normandy).
In October 1875, Jean-Pierre Haag and his wife are renting a house with an artist workshop located on 36 “Route de Paris-Amiens” (Paris to Amiens road), next to the “ruelle à Boudet” (the Boudet alley).
Jean-Pierre Haag was very erudite and interested in the village of Ecouen history. On July 10th 1902, a journalist of “Le journal du Dimanche” (the Sunday newspaper) wrote “He own precious documents concerning the massive castle standing next to his place”.
His son made, to the city of Ecouen, donation of the painting “Rouen, vue des galeries de l’église Saint-Ouen” (Rouen, view from the Saint-Ouen church galleries).