When she was growing up in Paris, Pauline Baer de Perignon was always told the same story about her great-grandfather, Jewish art collector Jules Strauss. Strauss — a German Jew living in Paris — owned a trove of Impressionist pictures by Renoir, Degas, Monet and many others. But the stock market crash of the 1930s forced him to sell much of his collection, leaving his heirs nothing. He died in 1943 of old age.