From the Kennedys to the Clintons to the unfortunate shark victims of Jaws, Martha's Vineyard, an island off the Massachusetts coast, has long conjured visions of well-heeled, sunburned Caucasians swarming its beaches and boardwalks in Top-Siders and pastel shorts. Yet when President Barack Obama and his family descend on this dune-swept summer playground the last week of August, they'll also find an island of rich diversity and harmonious race relations.
"Martha's Vineyard is the most integrated community I have ever experienced," says Harvard scholar Henry Louis Gates Jr. The island's minority population isn't huge (of its 65,000 summer residents,...