This universal piece has become a suitcase staple.

What do ancient Greeks and Romans, Viking marauders, even dignitaries of Star Trek's Klingon Empire have in common?The tunic. This simple, versatile top with its flattering length was worn as early as the second century B.C., but it wasn't until the late 1960's—when jaunts to Marrakesh and Rishikesh became de rigueur for the style set—that the look took hold in the States. Fast-forward to 2004: Tory Burch's modern version debuted and helped make it fashionable again. Inspired by a caftan she found at a vintage boutique in Paris, Tory Tunics now come in bold solids, ethnic prints, and materials ranging from linen to terry cloth. Long shirt?Short dress?Beach cover-up?Check. When it comes to travel, the tunic is an essential.