Brunswick (clothing)  A Brunswick gown or Brunswick is a two-piece woman's gown of the mid-eighteenth century. The Brunswick comprises a hip-length jacket with a high neckline and a hood, worn with a matching petticoat. The jacket sleeves consist of an upper sleeve with flounces at the elbow and a tight, wrist-length lower sleeve. The Brunswick is one of several informal jacket-and-petticoat costumes popular in the later 18th century, derived from working class costume but made up in fine fabrics. Originating in France (based on a German fashion), the Brunswick was also popular in England and the United States as a traveling costume.