The Morozov brothers were great-grandchildren of a serf. By the end of the 1800s they were two of the world’s greatest collectors of Western art. Mikhail Morozov brought the first Van Gogh to Russia. His brother Ivan built an unrivaled collection of Gauguins. They went on to snap up work by greats from Europe—Monet, Cézanne, Matisse, Picasso, Bonnard—as well as the work of modern Russian artists. Now coming to France, loans from the Hermitage, the Pushkin, and the State Tretyakov Gallery make it possible to see the exceptional collection back together outside Russia—a first. —E.C.