Married to blue-blooded Robert Livingston “Topper” Mortimer and with a family lineage supposedly dating back to Thomas Jefferson, Tinsley Mortimer used to personify “society.” She spent the millennium’s early years walking red carpets at galas, fashion shows and charity events and became one of the most photographed women in New York City. But this proto-Paris had something that set her apart from the other upper-crust ladies who lunch: she had ambition. She was one of the first to figure out how to monetize being famous for nothing in particular—and she didn’t even need a sex tape to get her there. She just kept on adding hyphens to her self-description: now, she’s a handbag designer-socialite-businesswoman-author-reality show star (the first of which led to success in Japan and the last of which, the CW’s High Society, was a colossal failure), proving that an oft-photographed face can be enough to launch a worldwide brand. Every single Real Housewife owes Ms. Mortimer a debt of gratitude for blazing that trail.