In 1941, Jacob Lawrence, then just 23 years old, completed a series of 60 small tempera paintings with text captions about the Great Migration, the mass movement of black Americans from the rural South to the urban North that began in 1915-16. Within months of its making, the Migration Series was divided between The Museum of Modern Art (even-numbered panels) and the Phillips Memorial Gallery (odd-numbered panels). The work has since become a landmark...