Georges Kars portrait of Berthe Weill, 1933, private collection © Maxime Champion

When Jewish art dealer Berthe Weill was forced to close her Parisian gallery and go into hiding during the Occupation of France, she had already helped build the careers of artists like Pablo Picasso, Henri Matisse, Amedeo Modigliani and Diego Rivera, as well as female including painter Suzanne Valadon, African-American sculptor Meta Vaux Warrick Fuller and Émilie Charmy, known for her portraits.