Wallis Simpson in Schiaparelli's "Lobster Dress", by Cecil Beaton, 1937

Photographed in France for Vogue magazine, just prior to her marriage to the Duke of Windsor, the newly-ex-King Edward VIII.  The graphic design of Schiaparelli's famous dress was by Salvador Dalí.

Though it's often cited as the dress, this is not the same copy worn by the soon-to-be Duchess; the decoration
on the bodice is on the opposite side and Mrs. Simpson's waistband is of a narrower proportion.